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C. Morphology 
1. Vegetative Cells. 
(а) Form: spheres, short rods, long rods, filaments, commas, short 
spirals, long spirals, curved. 
(б) Arrangement: single, pairs, chains, fours, cubical packets. 
(c) Limits of size-size of majority. 
(d) Ends: rounded, truncate, concave. 
2. Capsules. 
(a) How stained_ 
3. Motility. 
4. Endospores: present, absent. 
(a) Location of endospores: central, polar. 
(b) Form: spherical, elliptical, elongated. 
5. Staining reactions. 
See Exercise 27. 
6. (a) Is the organism Gram positive? 
(b) How does the per cent of acid compare with that produced by 
Streptococcus lactis.V 
(c) Does the organism produce spores? 
(d) How does the odor of the milk cultures compare with those 
fermented by Streptococcus lactis.V 
(e) What is the Wisconsin curd test? 
(0 What is its purpose? 
(g) Why are the curds kept at a high temperature? 
(h) Why is rennet added to the milk to be tested? 
(i) Do the bacteria remain in the curd or pass into the whey? 
(j) Why is dirty milk objectionable for butter and cheese making? 
( k ) In what way does the action of Aerobacter aerogenes upon 
milk differ from that of Streptococcus lactis ? 
(/) How is Aerobacter aerogenes related to the quality of milk? 
(, m ) What is the habitat of Aerobacter aerogenes ? 
