DESCRIPTION OF CLEPSINE PLANA. 



C. O. WHITMAN 



This species, as already stated in the foregoing paper on 

 Hypodermic Impregnation, agrees in some features closely with 

 C. parasitica, as described by Say ^ and Verrill ^ ; but the points 

 of agreement are not sufficient for identification ; for I have four 

 quite distinct species, — and I have reason to think there are at 

 least several more, — each of which comes about equally near the 

 characters said to belong to C. parasitica. In view of the fact 

 that we have several large species of Clepsine which agree in 

 having a single pair of eyes, a median yellow vitta, and marginal 

 yellow spots, I am led to doubt the identity of Verrill's C. para- 

 sitica with that described by Say. Say says, "This leech is 

 frequently found in the lakes of the Northwestern region, adher- 

 ing to the sternum, or inferior shell, of tortoises (Emys), particu- 

 larly to that of E. gcographica of Lestiair." Verrill's specimens 

 were found in "West River, near New Haven, Conn., on the lower 

 side of floating wood, and at Norway, Me." I have found two 

 quite distinct species of these large Clepsines in the vicinity of 

 Milwaukee, either of which may, or may not, be Say's species. 

 I have two eastern species, quite distinct from each other and 

 from the two Wisconsin species ; one from Charles River, 

 Watertown, the other from a pond in Worcester. Whether 

 one, or the other, or neither of these is identical with Verrill's 

 species, I am unable to say. 



Say mentions as the constant characters: "A yellow vitta 

 before ; quadrate marginal spots each side ; beneath with about 

 eleven longitudinal lines ; ocular points two." Then comes the 

 following description : " Body dilated when at rest, narrowed 

 before ; above varied with dull yellowish and blackish brown ; 



1 Majo7- Long's Expedition to the Source of St. Peter's River,, etc., in 1823. Keat- 

 ing's compilation, Vol. II, Appendix, p. 14. London, 1825. 



2 Synopsis of the North American Fresh- Water Leeches. Professor Baird's Report 

 for 1872-73, p. 678. The same description was given in tlie American Jour. Sc. and 

 Arts, Vol. Ill, February, 1872, p. 128. 



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