‘CHAPTER IIL. 
TAXONOMY. 
POINTS TO BE OBSERVED IN THE STUDY OF BACTERIA. 
The following scheme gives an idea of the points to be noted in the description of 
an organism together with some of the more common descriptive terms. 
CULTURE CHARACTERS. 
1. GELATIN PLATE: 
A. Surface colonies. 
a. Form: Punctiform, too small to be defined by naked eye; circular; oval; 
irregular; fusiform; cochlate, twisted like a snail shell; amoeboid, very irregular like 
changing forms of amoebae; conglomerate, an aggregation of colonies. 
b. Size, expressed in millimeters. 
c. Surface Elevation: flat; spreading; thin; raised, growth thick with abrupt, 
terraced edges; convex, surface segment of a circle but very flatly convex; pulvinate, sur- 
face the segment ofa circle but decidedly convex; capitate, hemispherical; rough, irregular 
elevations and depressions; contoured, like the undulating surface of a relief map; papil- 
late, horn like projections; rugose, wrinkled; alveolate, depressions separated by. thin 
walls; pitted; sulcate, ridged or furrowed. , 
d. Consistency: thin; membraneous, thin, dry, separating from medium; coria- 
ceous, thick like leather or parchment; viscous, ropy; slimy; gelatinous; brittle. 
e. Color: transparent; vitreous, transparent and colorless; oleaginous, trans- 
parent and yellow, olive to linseed oil colored; resinous, transparent and brown, varnish 
or resin colored; translucent; paraffinous, translucent and white, ‘porcelaneous; opales- 
cent, translucent, grayish-white by reflected light, smoky-brown by transmitted 
light; macreous, translucent, grayish-white with pearly lustre; sebaceous, trans- 
lucent, yellowish or grayish-white, tallowy; butyrous, translucent or yellow; 
ceraceous, translucent and wax colored; opaque; cretaceous, opaque and _ white; 
chalky, dull without lustre; glossy, shining; fluorescent; iridescent. 
f. Margin (To be determined by low power of microscope): entire; undulate; 
repand; erose, finely eroded as if gnawed; lobed; articulate; laciniate, cut jaggedly into 
deep narrow lobes; lacerate, cut variously into irregular segments; jfimbricate, edge 
bordered by slender processes thicker than hairs; ciliate, tufted; floccose, wooly, filaments 
in fleecy masses; curled, filaments in locks or ringlets: filamentous, consisting of loosely 
placed, interwoven filaments, not so dense as floccose. 
g. Internal structure (To be determined by microscope): homogeneous, uniform 
throughout; concentrically zoned; marmorated, traversed by veins as in some kinds of 
marble, marbled; finely punctate; areolate, marked out with small spaces, reticulate; 
moruloid, having the character of a morula, resembling a mulberry; segmented; finely 
granular; coarsely granular; grained, as in lumber; curled, composed of twisted bundles 
of parallel filaments as in locks or ringlets; floccose; filamentous. 
h. Change in Medium: consistency; color; odor. 
