THE LEECHES OF MINNESOTA 125 



metamerism in its pattern and no tendency toward the formation of 

 longitudinal stripes, the pigment being quite as continuous across the 

 middle line as elsewhere. Except in the very heavily blotched speci- 

 mens, in which a few spots occur, especially toward the margins, the 

 ventral surface is immaculate. 



Habits — The exact geographical range of this species is not yet 

 known but it is especially characteristic of the Mississippi Valley and 

 the lake region drained by the headwaters and tributaries of that river. 

 It is exceedingly abundant in Wyoming, Wisconsin and Minnesota, 

 but is known to extend as far south as Alabama. The stomachs con- 

 tain large numbers of insect larvae, which appear to furnish the chief 

 sustenance, but also various species of Oligochseta, aquatic snails etc. 

 No opportunity has been afforded me to study the habits of this species 

 but there is no reason to believe that they differ materially from those 

 of E. punctata. Verrill has described the egg cases as "broad oval or 

 elliptical, terminating in a point or mucro at each end, flat below, 

 smooth and slightly convex above, with a thin margin. They were 5.5 

 mm. to 8 mm. long by 3.5 mm. to 4 mm. broad." 



Genus Dina R. Blanchard. 



Size rather small ; not greatly depressed posteriorly. Sperm 

 duct not forming a long anterior loop reaching to ganglion XI ; atrial 

 cornua small. Last annulus of each complete somite obviously en- 

 larged and subdivided. 



Dina parva. sp. nov. 

 (Plate V. figs. 33, 34; Plate VI, figs. 41, 43.) 



Description — A number of small and imperfectly preserved leech- 

 es from Gull Lake show characters which readily distinguish them 

 from any species of Dina' previously described. The species exhibits 

 certain resemblances to Nephclis fervida Verrill, and may indeed prove 

 to be that species instead of the one which was so identified in my 

 paper on the leeches of Illinois. There is nothing in the original 

 description of N. fervida except the size which will permit one to 

 discriminate between the two. 



None of the specimens at hand exeed an inch in length in the 

 partly contracted state and if alive and extended would not be more 

 than one and one-half inches. Posteriorly the body is relatively wide 

 and flat but anteriorly becomes nearly circular behind the mouth. The 

 mouth and lips have the customary form. Unlike most of our Amer- 



