1884.] NATURAL SCIENCES OP PHILADELPHIA. 41 



February 26. 

 The President, Dr. Leidy, in the chair. 

 Twenty persons present. 



The following were presented for publication : — 



" On an Ammonite from the Carboniferous formation of Texas," 

 by Prof. Angelo Heilprin. 



'' The Tertiary Geology of Eastern and Southern United 

 States," by Prof. Angelo Heilprin. 



Messrs. Geo. W. Fiss and Francis E. Emory were elected 

 members. 



Distoma and Filarise. — Prof. Leidy directed attention to some 

 parasitic worms presented this evening. Some of these were 

 supposed to be leeches from the mouth of the alligator. Hero- 

 dotus states that the crocodile of the Nile has the inside of its 

 mouth always beset with leeches. The existence of the leech has 

 been confirmed, and is known as the Bdella nilotica. The present 

 specimens, however, do not belong to a leech, but pertain to a 

 species of Z'ls/o/^ia, apparently not previously described. It may 

 be named and be distinguished by the characters as follows : — 



Distoma oricola. Body elongated elliptical, moderately wider 

 and thicker posteriorly, and ending in a blunt, angular extremity, 

 convex dorsally and flat ventrally, unarmed, smooth or minutely 

 wrinkled transversely. Mouth subterminal, and enclosed with a 

 reniform lip succeeded by a linear annulus. Acetabulum large, 

 globular, included at the anterior fourth of the body, and openino- 

 ventrally by a conspicuous central aperture. Generative orifice 

 ventral, at the posterior fourth of the body. Length, 15 to 20 

 mm. ; breadth, 3 mm. Eight specimens obtained from the mouth 

 of the alligator, A. mississippiensis, in Florida, by Mr. Stua'-t 

 Wood. 



Accompanying the specimens is a fragment of the tongue 

 marked with circular scars, apparently due to the worms. The 

 alcoholic specimens in their present condition are incurved, with 

 the lateral margins inverted, and the included acetabulum pro- 

 duces a conspicuous dorsal eminence. 



Of several Filariie exhibited, two, a female and a male, pertair^ 

 to the species Filaria horrida, Diesing. The former is 28 inclies 

 long, the latter 11 inches. They were obtained by Dr. He my C. 

 Chapman, from the thorax of the American ostrich, Bhea ameri- 

 cana. The other specimens were obtained by Mr. P. L. Jouy, 

 from the abdomen of Strix brachi/otus. They consist of fou;-. 

 females from 12 to 14 inches long and a half a line thick, 

 and two males 2^ inches long and one-fourth of a line thick. 



