THE OVARY AND THE EGGS. 132 
during the breeding season than at other times; the large 
brownish-yellow eggs become conspicuous in the ovary, 
Fig, 32.— Astacus fluviatilis —A, a two-thirds grown egg contained in 
its ovisac (x 50); B, an egg removed from the ovisac (x 10); 
C, a portion of the wall of an ovisac with the adjacent portion of 
the contained egg, highly magnified; cp, epithelium of ovisac ; 
gs, germinal spots ; gv, germinal vesicle; m, membrana propria ; 
”, vitellus ; vm, vitelline membrane ; 1, stalk of ovisac. 
and the testis assumes a milk-white colour, at this 
period. 
The walls of the ovary are lined internally by a layer of 
K2 
