CONJUGATION IN THE CRAYFISH, CAMBARUS AFFINIS 247 
Fig. 2 Diagrammatic cross section of male and female in conjugation to show 
mode of attachment of hooks. 
After the above preparation the male settles down against the 
female and tries to fasten the hooks to the bases of the female legs. 
Holding the left legs of the female in his right claw and her right 
legs in his left claw the male tries to make fast the hooks that are 
on the third joints of the third legs to the grooves at joint of first 
and second segments of the third legs of the female. These 
grooves are accentuated by the fact that the female legs are bent 
up dorsally. In accomplishing this the male no longer stands up 
high above the female but brings his ventral surface as near as 
possible to the thorax of the female. If the two animals are at 
