Fie. 55. 
55a. 
56. 
56a. 
56. 
56c. 
Ove 
58. 
EXPLANATION OF PLATE LI. 
Leptinus testacevs, lateral view. 
5a » , dorsal view. 
Stenichnus collaris, lateral view. 
st 4 » ventral view of apex of median lobe 
with sac slightly evaginated. 
Stenichnus collaris, ditto, lateral view. 
ae » » lateral view with sac wholly evagin- 
ated, or nearly so. . 
Eumicrus tarsatus, lateral view. 
Physa inflata, lateral view, with sac evaginated. 
Descriptions on pp. 506-510. Explanation of the letters used 
uniformly on pp. 481-483. 
