The Elements of Bacteriological Technique Part 70

Flat: Thin, leafy, spreading over the surface (Fig. 143, a).

Effused: Spread over the surface as a thin, veily layer, more delicate than the preceding.

Raised: Growth thick, with abrupt terraced edges (Fig. 143, b).

Convex: Surface the segment of a circle, but very flatly convex (Fig.

143, c).

Pulvinate: Surface the segment of a circle, but decidedly convex (Fig.

143, d).

Capitate: Surface hemispherical (Fig. 143, e).

Umbilicate: Having a central pit or depression (Fig. 143, f).

Conical: Cone with rounded apex (Fig. 143, g).

Umbonate: Having a central convex nipple-like elevation (Fig. 143, h).

2. _Detailed Characters of Surface_:

Smooth: Surface even, without any of the following distinctive characters.

Alveolate: Marked by depressions separated by thin walls so as to resemble a honeycomb (Fig. 144).

Punctate: Dotted with punctures like pin-p.r.i.c.ks.

Bullate: Like a blistered surface, rising in convex prominences, rather coa.r.s.e.

Vesicular: More or less covered with minute vesicles due to gas formation; more minute than bullate.

[Ill.u.s.tration: FIG. 143.--Surface elevation of colonies: a, Flat; b, raised; c, convex; d, pulvinate; e, capitate; f, umbilicate; g, conical; h, umbonate.]

[Ill.u.s.tration: FIG. 144.--Types of colonies--alveolate.]

Verrucose: Wart-like, bearing wart-like prominences.

Squamose: Scaly, covered with scales.

Echinate: Beset with pointed prominences.

Papillate: Beset with nipple or mamma-like processes.

Rugose: Short irregular folds, due to shrinkage of surface growth.

Corrugated: In long folds, due to shrinkage.

Contoured: An irregular but smoothly undulating surface, resembling the surface of a relief map.

Rimose: Abounding in c.h.i.n.ks, clefts, or cracks.

(D) ~Internal Structure of Colony~ (_Microscopical_).--

Refraction Weak: Outline and surface of relief not strongly defined.

Refraction Strong: Outline and surface of relief strongly defined; dense, not filamentous colonies.

[Ill.u.s.tration: FIG. 145.--Types of colonies: a, Grumose; b, moruloid; c, clouded.]

1. _General_:

Amorphous: Without any definite structure, such as is specified below.

Hyaline: Clear and colourless.

h.o.m.ogeneous: Structure uniform throughout all parts of the colony.

h.o.m.ochromous: Colour uniform throughout.

2. _Granulations or Blotchings_:

Finely granular.

Coa.r.s.ely granular.

Grumose: Coa.r.s.er than the preceding, with a clotted appearance, and particles in cl.u.s.tered grains (Fig. 145, a).

Moruloid: Having the character of a mulberry, segmented, by which the colony is divided in more or less regular segments (Fig. 145, b).

Clouded: Having a pale ground, with ill-defined patches of a deeper tint (Fig. 145, c).

[Ill.u.s.tration: FIG. 146.--Types of colonies: a, Reticulate; b, gyrose; c, marmorated.]

3. _Colony Marking or Striping_:

Reticulate: In the form of a network, like the veins of a leaf (Fig.

146, a).

Areolate: Divided into rather irregular, or angular, s.p.a.ces by more or less definite boundaries.

Gyrose: Marked by wavy lines, indefinitely placed (Fig. 146, b).

Marmorated: Showing faint, irregular stripes, or traversed by vein-like markings, as in marble (Fig. 146, c).

Rivulose: Marked by lines like the rivers of a map.

Rimose: Showing c.h.i.n.ks, cracks, or clefts.

[Ill.u.s.tration: FIG. 147.--Types of colonies--curled.]