96 



[Oct. 



October 27th. 

 Dr. MoE-TON, President, in the Chair, 



The Committee on Mr. Deane's paper, " On the Fossil Foot-prints 

 of the Connecticut River,'' reported in favor of publication in the 

 Journal. 



The Committee on Dr. Townsend's description of a new American 

 Wolf, (Lupus gigas, Townsend,) reported in favor of publication in the 

 Journal. 



The Committee on the following papers by Dr. Leidy, read at the 

 meetings of October 1, Oct. 8th, and Oct. 15th, 1850, reported in 

 favor of their publication in the Proceedings. 



Contrilutions to Hehniiithology . 

 By Joseph Leidy, M. D. 



1. LiGULA Tritonts. Body ribbon-like, thin, translucent, nearly smooth, 

 faintly yellowish white, posteriorly obtusely rounded. Head thickened, rounded, 

 transversely corrugated, yellowish; extremity triangularly rounded, laterally 

 compressed, front and back, with a short, longitudinal, contracted depression. 



Whole length 1 in. 9 lines; breadth of body l-3d line, thickness l-12th line; length 

 of head 1 line, breadth l-4th line, thickness l-9th line. 



Habitation and Remarks. This species was sent to me by my friend Prof. 

 S. F. Baird, of Carlisle, with the note " Found embedded in the muscles of the 

 back of Triton (Cynops) dorsalis." It is the smallest species which has as yet 

 been discovered, and^he first among batrachian reptilia. The specimen sent to 

 me consisted of two fragments of the same individual preserved in alcohol. 

 Examined beneath the microscope it presented no trace of articulation or interior 

 definite organs. 



2. Pentastomum Didelphidis Virginianm, Body subcylindrical, curved one 

 third or one-half a circle, dorsum convex, bentrum concave, posteriorly narrowed 

 and constricted a short distance from the extremity, which is rounded. Color 

 white, opaque. Composed of forty or fewer annulations. Head posteriorly con- 

 vex, anteriorly plain or slightly concave; mouth nearly round; hooks simple, 

 situated in a curved line of which the mouth forms the centre. 



Whole length 3 to 5 lines, breadth 3-5th of a line ; annuli generally l-80th inch 

 wide ; mouth l-200th inch in diameter ; hooks l-200th inch long. 



Habitation and Remarks, I found 9 individuals of this entozoon, in C shaped 

 cysts, the circle being 2 lines in diameter, imbedded in the liver just beneath the 

 peritoneal surface, in Didelphis virginiana. It may probably be the Pentastomum 

 subeylindricum of Diesing,* which was found in cysts upon the liver of two South 

 American species of Didelphis, and several other animals, but the largest of 

 those found in our D. virginiana, is equal only to the smallest of P. subeylindricum, 

 and has not more than one-half the number of annulations. 



Annal. d. Wien. Mus. 1 p. 21. Ditjardin: Hist. Nat. des Helminthes p. 305. 

 Diesing : Systema Helminthum, Vol. I, p. 611. 



