uK THE LEECHES OF MINNESOTA 



divided form of the median portion and the widely divergent short 

 cornua. Tn these respects and also in the fact that the prostate gland 

 covers the dorsum of the median chamber as well as the bases of the 

 cornna, this species resembles D. microstoma most closely. 



Two distinct color varieties occur, both of which have a dusky 

 red color, during life, due to the blood. In one, pigment appears to be 

 r.early or quite absent, a condition which characterizes all of the 

 young and a few of the adults. The other and more usual variety 

 has the dorsum marked with more or less numerous minute black 

 flecks which vary greatly in number and somewhat in arrangement. 

 Many specimens are so little pigmented as to appear quite light col- 

 ored ; such are usually marked with a pair of dark longitudinal stripes 

 one on each side of a clear median area, in others these stripes become 

 very broad and in still others the whole dorsum except the margins 

 is deeply pigmented. 



Habits — So far as now known Dina fervida belongs to the fauna 

 of the Great Lakes and the immediately surrounding region, where it 

 is quite common. The food contents of the stomach consist largely 

 of tubificid worms and some insect larvae. Verrill has described the 

 egg capsules which are attached to the leaves of Nuphar as "broad- 

 oval or elliptical, above smooth and convex, translucent yellowish 

 brown, with a thin, flat lighter border, each end prolonged into a short 

 tubular neck, with a terminal orifice. Lower surface flat." They meas- 

 ure from 9.5 to 11.5 mm. long which seems remarkably large for a 

 species of the size of this. 



