EXPLANATION OF PLATE. 



The figures on this plate were drawn and colored from living examples taken at Put-in Bay during 

 the survey of Lake Erie. The figures are numbered from left to right: 1 to 3 above, 4 to 6 below. 



Fig. 1. Erpobdella j)unchita (Leidy) Moore. A young example. The pink color on the margin is 

 due to a wave of blood passing through the lateral vessel. X 4. 



Fig. 2. Glosniphonia stagnalig (Linnpeus) Blanchard. A nearly full-grown example. The luichal 

 gland is scarcely evident in the figure, and the stomach and intestine (containing little or no lilood) 

 are pale yellow. X 8. 



Fig. 3. Placohdella picUt (Verrill) Moore. A small and pale specimen, with the branched gastric 

 eseca very distinct. X 4. 



Fig. 4. Glo:<sij'lii)iiin riiiN/i/aiKila (Linnseus) Johnston. A small and lightly pigmented example, 

 with the dark paramedian lines very little developed. X 10. 



Fig. 5. Glo.ii<ipliniii,( fiisi'ii Ca.stle. A full-grown example of the lined variety, with the stomach 

 and intestine partially tilled with blood. X 15. 



Fig. 6 IHna fervida (Verrill) Moore. A nearly full-grown pale specimen, with three pairs of eyes 

 and an additional one on the right side. The red color is due to the blood, seen through the trans- 

 parent tissues. Fully extended. X 3. 



