112 
THIRTEENTH REPORT. 
taken were carrying eggs and one besides the type bore young. The 
measurements of eight females collected with the type are as follows: 
Carapace 
Length 
16.G 
16.3 
18.0 
19.5 
17.4 1S.1 
15.0 
17.0 
Breadth 
18.0 
17.7 
19.1 
21.0 
19.5 20.6 
15.8 
19.0 
No males were collected. The species is named constrict us on account of 
the narrowness of the posterior portion of the abdomen. 
EXPLANATION OF FIGURES. 
Figure 1. Ciibaris icatlceri. A, ventral view of first and second side 
plates; B, dorsal view of head; C. second antenna; D, first maxilla; E. 
last two segments of body and uropeds, dorsal view; F, ventral view 
of pleotelson and left uropod. 
Figure 2. Hyallclla ornata. A, left second gnathopod of male; B, 
first antenna; 0, second antenna; 1>. telson ; E, uropod; F, first maxilla; 
G, second gnathopod of female; H, first gnathopod of male. 
Figure 3. Cambarus ruthveni. A, inner surface of first pleopod of 
male; B, outer surface of first pleopod of male; C, ventral surface of a 
part of the seventh and eighth thoracic segments of female showing the 
annulus ventralis and the spine on the ventral surface of eighth thoracic- 
segment of female. 
Figure 4. Trichodactylus const rictus. Dorsal view of type female and 
claw of another female. Photograph taken by E. W. Sink. 
Ann Arbor, Mich., April, 1911. 
