Text-fig. 1. 
The Formation of the Mammary Glands in Marsupials. 
a. Lenticular stage ; b. club-shaped stage, common to all mar- 
supials. c. and D. Later stages in the development of the first 
type. e. and F. Later stages in the development of the 
second type. h. Branching hollow part of secondary outgrowth. 
h. Portion of a hair. 1. Layer of columnar cells, t.p. Teat 
pocket, p. Primary outgrowth, i . e. hair-follicle, s. Secondary 
outgrowth, i . e. mammary gland anlage. t. Tertiary outgrowth, 
i. e. sebaceous gland anlage. Figs, a-e are adapted from 
Bresslau (8). Fig. f is from my own preparations of Dasyurus. 
