BY THE LATE CHARLES DABWIN. 177 



Cliiloe, Jan. 1835." The set comprises thirteen specimens, 

 mostly females, the longest of which does not exceed 3 inches. 

 It was Eudolphi who first suggested that the Ascaris found by 

 Lebeck in a Grangetic Dolphin belonged to the same species. 

 This view was confirmed by myself from an examination of Nema- 

 todes procured from a Flatanista gangetica by Dr. Jobn Ander- 

 son. I think it highly probable that the Ascaris found by Krefft 

 and Masters in a Dolphin captured in Port Jackson is of the 

 same species. If so, tbe worm occurs in DelpMnus phoccena, in 

 D. Forsteri, in Flatanista gangetica, and probably in Dolphins 

 generally. Be that as it may, the whole question of Cetacean 

 Nematodes requires careful revision. I will only at present 

 remark that the ova from Mr. Darwin's specimens are nearly 

 spherical, furnished with thin, transparent chorional envelopes. 

 They give an average diameter of -g-g-g- of an inch from pole to pole. 

 M. Dujardin, whose description of the species is the best on 

 record, found the eggs to be a trifle larger. 



The literature of this parasite is poor and much scattered. 



Lebeck.— In Neue Schrift. d. Berl. Gesell. Naturf. Fr., Bd. iii. S. 282 



[non vidi). 

 RuuoLPHi. — Entoz. Hist. Nat. vol, i. p. 1/0. Synops. Eat. 1819, 



pp. 49, 54, 296. 

 Dujardin.— Hist. Nat. d. Helm. 1845, p. 220. 

 DiESiNG. — Syst. Helm. vol. ii. 1851, p. 155. 

 Van Beneden.— Bull, de I'Aead. roy. de Belg. 1870, p. 119. 

 Krefft.— Trans. Entomol. Soc. N.S.W. for July 3, 1871, p. 8. 

 Cob BOLD. — Proceed. Zool. Soc. 1876, p. 279. Linn. Soc. Journ., Zool. 



1876, vol. xiii. p. 43. ' Parasites,' Lend. 1879, p. 426. ' List of 



Parasites,' Int. Fish. Exh. 1883, nos. 71, 73. 

 O. V. LiNSTOw. — Compend. 1878, S. 59. 



4. DiSTOMA IlfCEETA, n. sp. 



Body smooth, witb very fine tubercles in front ; oral sucker 

 oval, subterminal, nearly twice as large as the acetabulum ; 

 intestine simple, with wide caecal ends ; folds of uterus numerous, 

 reaching to within a sbort distance of tbe tail ; eggs oval, minute. 

 Length yV to ^". 



This small Trematode is catalogued by Mr. Darwin as a " "Worm 

 from moutb of a Snake pjlied to Coluber ; Maldonado, Eio Plata, 

 May 1833." I am reluctant to proclaim the species as new to 

 science, but after careful comparison witb the Distoma JBoscii 

 found by me in the mouth, trachea, and lungs of an American 

 Coluber that died at the Zoological G-ardens in 1858, I am 



LINN". JOURlSr. — ZOOLOGY, VOL. XIX. 15 



