218 Vniversitij of CalifoDiia Publications in Zoology [Vol. 11 



Thus it is to be observed that the recorded range of food 

 materials for nephelids is wide. I have kept snails {Limnea, 

 Planoriis, and Physa) and Dina microstoma in aquaria together 

 for weeks, but have yet to see the leeches attack a living snail. 

 Often they are to be seen twisting themselves around the snail, 

 but always, sooner or later, the snail successfully rids itself of 

 them. When a gash was cut into the foot of the snail with a 

 scalpel they were observed to feed on the injured part until 

 the snail withdrew into its shell. However, they fed vigorously 

 upon crushed snail. A young living earthworm was placed in 

 the dish with several Dina, with the result that it was lacerated 

 to death through the sucking action of the leeches and finally 

 completely eaten, a fragment at a time. Older earthworms met 

 with a similar though not so rapid and complete destruction. 

 A recently dead crayfish, with its body severed in two, was fed 

 to the voracious animals, which attacked it with as evident relish 

 as they later fed upon a freshly killed minnow cut in pieces, 

 and also one dead for a couple of days. A dead salamander 

 was fed to some hungry individuals and, while not vigorously 

 fed upon, yet it was partaken of by several of the leeches. The 

 same held true in the case of a Belostoma which had been dead 

 for a day or two. Thus the food of this species of leech serves 

 to point towards its being to a large extent a scavenger. 



Castle (1900) saj's of the leeches of the family Rhynchob- 

 dellidae to which the genus Glossiphonia belongs : ' ' The smaller 

 speeias feed upon snails, Crustacea or other small fresh-water 

 animals." Harding (1910) states in regard to Glossiphonia 

 complanata: "It is parasitic chiefly upon Limnea and Planorhis, 

 but also attacks other fresh-water mollusks, the larvae of Chiro- 

 nomus and probably aquatic annelids." It was found possible 

 to keep G. stagnalis in good condition for weeks by feeding them 

 earthworms, from which they sucked the blood. No feeding 

 experiments were conducted upon Hemiclepsis occidentalis. Of 

 a related form, Hemiclepsis marginata, Harding saj's: "This 

 species is a fish parasite. Apathy states that it attacks the smaller 

 species of carp." 



