Practical Taxidermy Part 39

Wings with scales.

Horns clubbed at the apex.

Middle nerve of fore-wing 4-branched.

The whole "Synopsis," published at a s.h.i.+lling, by the authorities of the Liverpool Museum, is well worth reading. It contains a store of information, not the least interesting being the Greek and Latin derivations of the scientific names. I am especially glad to see that the Greek characters are not barbarously replaced by English "equivalents," which nearly always fail to give the key to the roots.

[Footnote: I noticed "Ocnai gunaike" written in a scientific work lately, and I thought I never saw a sentence so ugly and so unlike what it would be if written in Greek characters or properly p.r.o.nounced.]

The cases themselves are excellently adapted to show the specimens, and the plan--if we except the division labelled "British," which might be advantageously altered, I think, to "Animals belonging to the above group (etc.), found also in Britain"--is admirable. Not only are objects dried, mounted, or shown in spirits, but first-cla.s.s coloured drawings of such creatures as Medusae, etc, are provided. This is, I am sure, a step in the right direction, and I so recognise the importance of this, that I am preparing charts of parts, etc, of animals as keys to their structure, and also enlarging minute forms under the microscope, to be placed in position in the invertebrate cases for the Leicester Museum.

Another very fine feature of the Liverpool Museum, and worthy of imitation, is the manner in which the osteological preparations are managed. Not only are complete skeletons of mammals shown, but parts for comparison--that is to say, there is a large series of skulls of various mammals, birds, reptiles, and fishes, and, again, leg and arm bones, and their parts, arranged side by side; hence you may compare the fore-limb of the human subject with that of a monkey, a lion, a whale, a marsupial, a bird, a reptile, or a fish. [Footnote: Of course, all this may be seen in the Museum of the College of Surgeons, or at Oxford or Cambridge, etc, but these are special inst.i.tutions, and I am merely taking provincial general museums as my standpoint.]

It is needless to say--taking into consideration the fact that these are prepared under the direction of the curator, Mr. Moore, and his accomplished family--that all are beautifully arranged and cla.s.sified.

In short, Liverpool is to be congratulated on its collections of bones and invertebrates. Turning, however, to the vertebrates, we see that, although the management begins to recognise the importance of "pictorial" mounting, it is done in a half-hearted manner--isolated groups here and there, on square boards, placed in the general collection amongst the birds, on pegs, serving only to render the latter more conspicuous in their shortcomings. This system of Liverpool is being copied at Nottingham, Derby, and other places, and was being copied also at Leicester, but not being, to my mind, half thorough enough, has been discarded for the more ambitious--certainly more effective--and quite as scientific method of arranging the vertebrates pictorially, and in their proper sequence in orders and families, endeavour being made to represent specimens of each genus also, where practicable, in this manner.

As will be seen, in making a brief resume of what has gone before, I am in favour of large, top-lighted rooms, painted in a light neutral tint, well warmed; cases built in oak, with single sheets of plate-gla.s.s not less than 7 ft. 6 in. by 5 ft. or 8 ft. by 5 ft. 4 in, artificially lighted by pendants shaded from the eye; the vertebrates to be pictorially mounted both in the "general" and "local"

collections, but, of course, zoological sequence and science not to suffer in consequence; I think that the "local" and "general" typical collections should be entirely distinct though close to each other in the same room for comparison; that extreme care should be taken in the collection and mounting of the animals inhabiting the district, and that no opportunity be lost of making this latter as complete as possible; that anything for which the locality is famed, be it fossils or antiquities, be the chief motif of any provincial museum; that, failing this, some groups or forms be collected to establish a monograph, such as Norwich is doing with its Accipitres; that, where practicable, bones and complete skeletons of animals should be collected, as being, of the greatest service to all students, be they medical or biological.

Also that explanatory charts and lists take the place of labels for the vertebrates, and that all information as to range and distribution of species be given. Further, that anatomical diagrams and figures explanatory of the structure and form of animals be provided, together with all facilities for the study of biology from a scientific stand-point. I have also laid down the axiom that a very small museum must and should confine itself to objects collected in its immediate vicinity, but that a fairly large museum would ever be in a disjointed and unfurnished state if it relied solely on such specimens. It must, therefore, have a general collection; and care should be taken in the selection of specimens so that they may fill up the blanks occurring in the "local."

Another thing I am quite a.s.sured of; it is that the management should exercise a wise discretion in refusing unsuitable objects (chiefly of ethnology) or duplicates of common forms, and never receive a collection if fettered with the condition that "it must be kept separate." Order, method, neatness, and careful cataloguing I say nothing about, for I a.s.sume that all princ.i.p.als must practise these virtues to do any good whatever with the collections entrusted to their care.

Scanner's remarks.

This book seems to have been printed about 1885. I got my copy when I was still a teenager (nth-hand; I am not really as old as all that!) and have greatly enjoyed the enlightened, yet practical and down-to-earth att.i.tude of the writer. It seems to me a fine example of late Victorian instructional material of the unpretentious persuasion.

Some of Browne's views were ahead of his time in terms of compa.s.sion and conservation, so I urge modern readers not to sneer at what they see as his out-of-date interest in "stuffed animals". Nor should they take too patronising an att.i.tude to Browne's long paragraphs and occasionally strained concordances; he was not a professional writer and he produced a fine, readable, and useful work. Both to the biologist and historian of science, the book remains useful to this day, and, as books of that period disappear for good, I hope, in scanning it, to prevent a sorry loss to our generation and to those who follow us. Though I nowhere edited his wording or punctuation in any other way, no matter how much self-control this occasionally demanded, I did split a lot of paragraphs, especially when they spanned pages and thereby confused lines of thought.

In transcribing this book I have generally kept as truly to the original as I could, including when Browne's (or possibly his editors') conventions for the use of quotes and parentheses set my teeth on edge. However, for lack of convenient font characters and sophistication of scanning software, I have converted most of the vulgar fractions to decimals. The others I have represented with slashes, so that say, a value of one third might appear as 1/3. Similarly, I have split ligatured characters such as the ligatured "ae" and "oe" frequent in late Latin in particular. Also, following a practical and common convention, I have replaced the umlaut with a following letter "e".

Thus "Moller" becomes "Moeller".

Browne frequently cross-referred readers to pages in the book. As pages got changed in scanning and editing, I have changed such page references mainly to chapters or similar references.

There were several places where changes (generally advances, I hope!) in technical biology, or possibly slips that Browne made in matters outside his speciality, led to errors. I have not corrected these in the text of course, nor do I discuss many of them. After all, most readers who can recognise the errors in modern terms do not need my a.s.sistance in correcting them, and to the other readers they would hardly matter. Here however are comments on a few arbitrarily chosen points, in no particular sequence:

* Browne seems to have worked before hydrogen peroxide became generally available, or possibly before its bleachng powers were recognised. For bleaching most biological specimens, especially bones and the like, hydrogen peroxide is in every way better, less offensive, less corrosive, and less damaging to tissues, than hypochlorite. Soaking even badly yellowed teeth in say, a "five volumes" concentration (about 1% to 2%) of peroxide for a few days or weeks, whitens them beautifully without damage or rotting of tissues.

You might find that other peroxide compounds, such as perborates, work better still, but I have not yet had occasion to use them.

Other methods of bleaching only are worth trying when the specimens happen to contain a particular pigment that does not respond well to peroxide bleaching. Some such pigments are better bleached with other chemicals, such as sulphites or hypochlorites.

* It takes some trawling through the book to discover that by "mites"

in insect collections, Browne probably means "booklice", i.e.

Psocoptera.

* Earwigs (Dermaptera) are not Hemiptera, as Browne cla.s.sed them.

Dermaptera and Hemiptera are not even closely related. The error is an interesting one however. It presumably arose from a nineteenth-century confusion of the hemelytra of the Hemiptera, with the short tegmina, the covering fore-wings of the Dermaptera, that protect their hind wings when they are not in flight. Hemelytra of Hemiptera are not really half-wings anyway, but protective fore-wings armoured for only about half their length. The two orders do not even resemble each other in appearance, anatomy, habits or ecological significance.

* Browne uses a few terms not easily to be found in every dictionary nowadays. Dowlas is (was) a coa.r.s.e kind of linen, but probably Browne referred to a strong calico in imitation of such linen. For "filister"

read "fillister"; according to more or less contemporary dictionaries, it is a misspelling. It turns out to be a type of rabbet plane used in making window frames and similar structures.

* For setting insects on a setting board, I was slightly surprised at Browne's use of "braces" and the like. Nowadays everyone I know uses strips of smooth, non-sticky, translucent paper or similar material for the purpose, and I had not realised that any other methods had been used in the past. The use of such strips is easy, fast and effective.

It permits one to set large numbers of insects almost in an a.s.sembly line fas.h.i.+on, working from the far end of the board towards oneself, laying the tape over the wings, blowing or gently dragging the wings into position, pinning down the tape, and proceeding to the next insect.

* If you get a small fish alive, then there is absolutely no way to set it more perfectly than by dropping it alive into rather strong acetic acid. This is not generally practical for say, a large salmon, but for anything of manageable size, it leaves the gills, jaws, and fins fully and stiffly extended. Strong formaldehyde has a similar effect, but not as good. Immediately the specimen is stiff and dead (a few seconds at most) remove it from the acid and rinse it gently with clean, cold water, then transfer it to a solution of ammonium carbonate, lime water, or similarly gentle alkaline material, to neutralise the acid before proceeding with whatever means of preparation you intended. See also the means I describe for preventing acid damage.

* If you happen to use hypochlorite or any other compound that releases chlorine, and you then wish to remove the residues, first rinse your specimens clean as well as is convenient, then soak them in very weak peroxide for a while. Hypochlorite and peroxide react with each other to produce free oxygen (harmless) and chloride (also harmless in any plausible concentrations). The effect is to neutralise any harmful or irritating residues or smell of chlorine.

* In at least one place I was surprised to see that Browne speaks of pinning insects exactly through the middle. Nowadays this is not widely done because one risks damaging structures on the median line of the specimen. Instead the common convention is to pin specimens somewhat to the right of the median, so that anything damaged on the right can generally be seen undamaged on the left. When setting beetles or the like, this usually means pinning them through the right elytron. Commonly one then may set the specimen with the left elytron and wing spread. Not all beetles will permit this of course, as many flightless species have their elytra fastened down, and some, such as many Scarabaeidae, flip their flying wings out pen-knife-like without noticeably raising the elytra.

* No doubt the non-toxic soaps and so on that Browne describes do work as advertised, but for keeping pests of dried material at bay, for protecting hides, preserved insects and so on, do not copy the recipes from this book. Though many of Browne's observations are in every way practical and intelligent, our current knowledge of safe, persistent, effective insecticides would not emerge for some fifty or sixty years after his death. And, please, please! Though Browne was realistic in his a.s.sessment of the dangers of the chemicals he describes, bear in mind that even his precautions were insufficient for modern purposes.

Above all, be very wary of the mercurial recipes he mentions!!! It is true that mercuric chloride is very effective, but I cannot think of a single modern reason to use it. Today we have much safer, more appropriate, materials at our disposal, including some very effective fumigants that Browne would have coveted.

* Note that among the substances that Browne fails to warn us against, are those that certainly are of low acute toxicity, but present serious risks of chronic medical conditions or cancer, unrecognised in his day. His much beloved "benzoline" seems to have been largely benzene, which nowadays is regarded as a carcinogen, and for many purposes too dangerous to handle. Before this became generally known I personally handled benzene in totally unacceptable ways, but so far I seem to have been lucky, and I seem to have given up tempting fate before I incurred dangerous symptoms.

* Browne seems to me a bit too cheerful about high-pinned insects being protected from some museum pests. High pinning might help a little, but it most certainly is nowhere near adequate. I have seen entire cases reduced to labelled pins standing among Dermestid beetle fra.s.s. Use modern insecticides and carefully sealed drawers or cases. I like the new pyrethroids, but keep in touch with museums to be sure you know the best current means of protection. Grease from pinned insects has caused me less of a problem than Browne describes, but possibly that is because I always have used the high-pinning techniques, never having known any other.

* When it comes to setting insects Browne was no doubt very artistic and very competent at producing a presentable specimen no matter what, but some of his procedures for cheerfully snipping insects and re-a.s.sembling them should be avoided. Such expedients could ruin specimens intended for the use of professional entomologists. For the requirements of biological studies, it is far more important to have a fully genuine specimen, no matter how badly disfigured, than a hopefully reconstructed mosaic, no matter how artistic. For some purposes one could use more radical "relaxing" procedures instead.

Browne seems to have used only cool water vapour or sometimes liquid water. Careful application of hot steam can relax most specimens that otherwise could not be re-set. One good trick (Beware of the risks of cuts and scalding if your apparatus should burst!) is to boil water in a closed vessel, leading the steam out into a tube, preferably of silicone rubber, tipped with a drawn gla.s.s tube or the blunted needle of a syringe. Direct steam at the parts that need relaxing. With practice you often can relax legs or wings one at a time, stopping as soon as they reach the desired position.

* Note too, that Browne is cheerful about mounting some insects by gumming their feet (tarsi) to card. For entomological purposes this has severe disadvantages. Nowadays professionals hardly ever use any means of setting that prevent one from examining a specimen from all sides. Even mounting them on a transparent material tends to interfere with proper examination. For most purposes pin the insects using what Browne called "flat" setting, high on the pin, with the label beneath.

Where this is not practical, such as for tiny specimens, there are other methods, which you may see described in manuals or used in museums.

* Note: Browne wrote in pre-decimal days, using largely the so-called Imperial units. This might raise difficulties in understanding his quant.i.ties. E.g. his dram or drachm (drm) probably was 0.125 ounce (roughly 3.5 grams). His pound would be sixteen ounces (oz.) of 28.35 grams, but his pint would be twenty fluid ounces (not 16 as in American pints!) Correspondingly his gallon would be ten pounds, not eight. A grain would be about 65 mg. Of other units and utensils apparently common in Browne's day, such as "six-pound Australian meat tins", or "goffering-irons", make what sense you may. A "wine-bottleful" was probably about 700 cc.

* Note: I have had little use for hexavalent chrome compounds but one thing I did notice in experimenting with a few of Browne's recommendations ("b.i.+.c.hromates", "chromic acid" etc), is that the merest few drops of such compounds (typically as a solution of pota.s.sium dichromate or chromate) added to water containing soft creatures such as molluscs, generally will kill them gently by paralysis and leave them relaxed. Usually almost anything else one uses, short of illegal or expensive drugs, causes such specimens to distort or contract into useless lumps. Once the chromate has thoroughly killed and relaxed them, say after an hour or two, the specimens can be fixed, preserved, or manipulated as required. You may wish to compare this method with the method that I describe for killing molluscs with boiled water.

* One effective way of killing molluscs, particularly gastropods, snails and the like, whether terrestrial, freshwater or marine, in fully extended form, is to put them into cool or barely lukewarm, freshly-boiled water that has been kept closely covered in airtight containers for cooling without permitting a lot of oxygen to re-dissolve in the water. First rinse the live specimens in fresh water to clean away superficial dirt and slime, then submerge them in the de-oxygenated water. Place some sort of grid or other barrier to ensure that they cannot get near the surface, and re-seal the container to keep air out. Leave them for at least twenty-four hours before transferring them to a preservative fluid or otherwise proceeding to deal with them. This method leaves them fully extended and firm, ready for dissection or for preservation for display. If you remove them too soon, they at first seem dead, but contract say, when a scalpel stimulates a still-living nerve.

* The cyanide bottle for killing insects certainly could be very useful, though I am not certain how widely such a dangerous substance would be available nowadays. Many forms of killing bottle have been used in the last century or so, and several are described in many handbooks. An old favourite handbook of mine is the British Museum Instructions to Collectors (Insects). Most killing bottles depend on some volatile liquid soaked into plaster, rubber or cotton wool. My own favourite was ethyl acetate, which is safe, inoffensive, and has several advantages, as long as the bottle and fluid are kept free from moisture. For some reason the presence of water seems to reduce its effectiveness at quickly immobilising specimens. Dry ethyl acetate paralyses most insects very quickly, even if it takes longer to kill them. For example, unlike many popular components of killing bottles, ethyl acetate leaves dead specimens relaxed.

* When you have treated wet specimens with anything acid, do remember to neutralise the acid residues as soon as possible. The same applies if you have preserved them with anything that gradually produces acid; For example, formaldehyde gradually reacts with oxygen to produce formic acid. In due course it destroys sh.e.l.ls, and even fine bones and teeth. As a buffer, ammonia is cheap, effective and safe in reasonable circ.u.mstances. However, it is too volatile to be a reliable buffer against long term acidity. Specimens preserved in formaldehyde can be protected in the long term by adding hexamethylenetetramine (otherwise known as hexamine, the product of ammonia and formaldehyde) to the liquid. A practical proportion is to add 100 grams of hexamine to a litre of concentrated formaldehyde solution (formalin). Dilute this solution before use, according the requirements of your particular application. If you cannot get hexamine, you can use strong ammonia (about 36%) solution, about 150 ml to 1 litre of formalin. In preparing to use such formalin, allow for the fact that in adding the ammonia you diluted the formalin by about one sixth. Alternatively, though usually less effectively, you could add some ammonium carbonate or sodium bicarbonate to the container. Sometimes a little oyster-sh.e.l.l grit or chalk will do for long-term buffering; it can be used together with the hexamine and can go on working after the hexamine is exhausted if the collection is poorly maintained. Use your good sense in adapting your measures to your needs.