PLATE I. 



Fig. 4. — Sewage Proteus. (About natural size.) 

 (a) Gelatine " shake "' culture. 24 hours' growth at 20" C. Gas bubbles. 

 {b) Gelatine " stab " culture. Twenty-four hours' growth at 20° C. 

 {c) Gelatine " stab ' culture. Forty- eight hours' growth at 20^" C. 



Fig. 5. —Proteus Vulgaris, (x 3,000.) 

 Impression preparation from "swarming islands "on gelatine. Twenty hours 



growth at 20^^ C. 



