314 PARASITES OF ANIMALS 



However, I succeeded in watching the growth of the embryos 

 until they had acquired well-marked digestive organs and 

 a length of -L", their size when emerging from 

 the egg-shell in the water having been about 

 jjg" only. The large strongyle (Eustrongylus 

 gigas) has been found in various organs of the 

 common seal. Of more interest are the Filarice 

 found in the heart of seals, which in many re- 

 spects resemble those obtained from the same 

 situation in dogs. Professors Joly, Leidy, and 

 myself, have each described a species, but ap- 

 parently our descriptions all refer to one and 

 the same parasite. It has also been seen by 

 Camill Heller. The close correspondency in 

 size and other characters of Leidy's Filana 

 spirocauda and my Filaria hcbetata leaves little 

 doubt as to their identity. As the worms were 

 both originally noticed by Leidy and Joly in 

 1858, I cannot pronounce upon the question 

 F.O. 59.-^m ". of priority of discovery. By Joly the worm 

 ml?e. a i'r e H\ *;i[e" was called F. cordis phoccB. In Leidy's and 

 Original - in my own specimens the males were four inches 



long, and the females six inches ; they extended up to 8" in 

 some of the American examples. The worms found by Prof. 

 Joly were all females. Professor Millen Coughtrey, who furnished 

 me with the seal's heart, stated that it was obtained from a male 

 hoodcap (Stemmatopus cristatus), a rare visitant of our British 

 coasts. This seal was captured on the Cheshire side of the 

 Mersey river. Leidy and Joly obtained their specimens from 

 Phoca mtulina. In the common seal have also been found 

 Ligula crispa, Schistoceplialus dimorphus, and Echinorhynchus 

 strumosus. In other seals a not uncommon tapeworm of the 

 Bothriocephalous type is that called Dibothrium Mans by 

 Diesing. To Prof. Krabbe I am indebted for a specimen of 

 Bothriocephalus fasciatus taken from Phoca hispida. There is a 

 nematode of frequent occurrence in P. hispida and P. grcpnlan- 

 dica. This is the Ophiostoma dispar of Rudolphi. In addition 

 to the above I can only add that P. barbata is infested by 

 Liorhynchus gracilescens, occupying the stomach, and by a tape- 

 worm, Tetrabothrium anthoccphalum, which is found in the lower 

 part of the large intestine. 



BIBLIOGEAPHY(NO. 46). Cobbold, "Description of F. hcbetata," 



