THE LEECHES OF MINNESOTA 77 



Habits — Glossiphonia nepheloidea is by no means an abundant 

 leech and has been until recently generally overlooked, a result 

 no doubt in large part due to its inconspicuous coloring and se- 

 clusive habits rather than its scarcity. Only four specimens, all 

 taken from Lake Pepin by means of a pump, represent the species 

 in the Minnesota collections. Whitman, Graf and Castle have found 

 it only in ponds in Massachusetts. In my experiences it occurs 

 much more numerously in running water among plants, particularly 

 along the muddy flats exposed at low water along the Delaware 

 River, associating with G. stagnalis, G. complanata and sometimes 

 other species. 



In appearance and movements it is much more worm-like than 

 any other species of Glossiphonia. Its weak suckers and deficient 

 musculature ill fit it for active creeping and, being incapable of 

 swimming and of a manifestly sluggish disposition, it moves about 

 but little and chiefly in the very unleechlike manner of crawling 

 through the ooze. When exposed in its place of concealment it 

 writhes and twists in a peculiarly helpless fashion, often for a long 

 time not even attempting to attach the suckers and never exhibit- 

 ing that decision of movement and promptitude to seek conceal- 

 ment which is shown by G. stagnalis. Its means of protection con- 

 sist largely in the very copious mucous secretion which envelopes 

 the body when irritated. 



Although, like G. stagnalis, this leech will feed on snails and 

 worms and even suck blood when the opportunity offers, it is es- 

 sentially a scavenger and feeds largely on the substance of dead ani- 

 mals and on ooze. 



Glossiphonia stagnalis (Linn.) Johnston. 



(Plate I. fig. 1.) 



I/irudo bioculata Bergmann ( 1757) 

 Hirudo stagnalis Linnaeus ( 1758) 

 Clcpsinc modesta Yerrill (1872) 

 Hclobdclla stagnalis Blanchard (i896) 



Description — Glossiphonia stagnalis is a small leech some- 

 what larger and decidedly stouter than G. nepheloidea. Large 

 individuals may reach a length of an inch when fully extended and 

 in that state would be fully twice the width of a G. nepheloidea of 

 the same length. When contracted to one-half that length, which 

 is about the ordinary resting condition, they would be about three 



