The Elements of Bacteriological Technique - Part 71
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Part 71

4. _Filamentous Colonies:_

Filamentous: As already defined.

Floccose: Composed of filaments, densely placed.

Curled: Filaments in parallel strands, like locks or ringlets (Fig.

147).

(E) ~Edges of Colonies.~--

Entire: Without toothing or division (Fig. 148, a).

Undulate: Wavy (Fig. 148, b).

Repand: Like the border of an open umbrella (Fig. 148, c).

Erose: As if gnawed, irregularly toothed (Fig. 148, d).

[Ill.u.s.tration: FIG. 148.--Edges of colonies: a, Entire; b, undulate; c, repand; d, erose.]

Lobate.

Lobulate: Minutely lobate (Fig. 149, e).

Auriculate: With ear-like lobes (Fig. 149, f).

Lacerate: Irregularly cleft, as if torn (Fig. 149, g).

Fimbriate: Fringed (Fig. 149, h).

Ciliate: Hair-like extensions, radiately placed (Fig. 149, j).

Tufted.

Filamentous: As already defined.

Curled: As already defined.

[Ill.u.s.tration: FIG. 149.--Edges of colonies: e, Lobar-lobulate; f, auriculate; g, lacerate; h, fimbriate; i, ciliate.]

(F) ~Optical Characters~ (after Shuttleworth).--

1. _General Characters_:

Transparent: Transmitting light.

Vitreous: Transparent and colourless.

Oleaginous: Transparent and yellow; olive to linseed-oil coloured.

Resinous: Transparent and brown, varnish or resin-coloured.

Translucent: Faintly transparent.

Porcelaneous: Translucent and white.

Opalescent: Translucent; greyish-white by reflected light.

Nacreous: Translucent, greyish-white, with pearly l.u.s.tre.

Sebaceous: Translucent, yellowish or greyish-white.

Butyrous: Translucent and yellow.

Ceraceous: Translucent and wax-coloured.

Opaque.

Cretaceous: Opaque and white, chalky.

Dull: Without l.u.s.tre.

Glistening: Shining.

Fluorescent.

Iridescent.

2. _Chromogenicity_:

Colour of pigment.

Pigment restricted to colonies.

Pigment restricted to medium surrounding colonies.

Pigment present in colonies and in medium.

~Streak or Smear Cultures.~--

_Gelatine and Agar._--Note general points as indicated under plate cultivations.

_Insp.i.s.sated Blood-serum._--Note the presence or absence of liquefaction of the medium. (The presence of condensation water at the bottom of the tube must not be confounded with liquefaction of the medium.)

_All Oblique Tube Cultures._--

1. Colonies Discrete: Size, shape, etc., as for plate cultivations (_vide_ page 261).