PARASITES OF FISHES OF BEAUFORT, NORTH CAROLINA. ^25 



ADDITIONS TO THE HELMINTHOLOGY OF NORTH AMERICA. 

 ACANTHOCEPHALA. 



The adult form of Echinorhynchus sagittifer Linton is here recorded for the lirst 

 time. This name was assigned to certain immature forms which have been found on 

 the viscera of several of our food fishes. The adult was found at Beaufort in the 

 intestine of the cohia (Rachycentron oanadus). 



At Woods Hole. Mass.. the most abundant species of Echino?'hynchus is the one 

 which I have referred to the species E. acus, which infests a large number of the 

 fishes of that region. It was not found at Beaufort, while E.pristis, not common at 

 Woods Hole, was found frequently and in .some 14 different hosts. 



NEMATODA. 



One new nematode is recorded — Filaria galeata sp. now. from the bonnet-head 

 shark {Sphyrna tiburo), 



The generic name Heterahis is used instead of Cucullanus for certain small 

 worms which I have recorded under the latter name in my Parasites of the Fishes of 

 the Woods Hole Region. In like manner the same generic name is used for some 

 small nematodes which I recorded in the above-cited paper as Ascaris {?) ■■</>. 



There is much need of systematic work on those nematodes which arc referred 

 by different authors to the genera Cucullanus, Dacnitis, and Heterakis. 



Immature nematodes, most, if not all, belonging to the genus Ascaris, were 

 found in 33 of the 59 species of fishes examined. So far as these have been studied 

 the most frequently recurring type is char cterized by having a diverticulum of the 

 bulbous base of the oesophagus which extends caudad and lies parallel to the intestine. 

 There is also a short diverticulum of the intestine which extends cephalad beside 

 the oesophagus (ties. 26-29, 33). Another type has only the intestinal diverticulum. 

 In it tin' basal bulb of the oesophagus is elongated instead of being nearly globular 

 as in the others, while the postanal region is usually transversely corrugated 

 (figs. 31, 32). 



CESTODA. 



Three new cestodes are recorded: Dibothrium tortum, Otobothrium insigne, 

 Rhynchobothrium plicatum. The first, from Synodus fattens, should perhaps be 

 referred to a new genus, between Monobothrvum and Dibothrium {Bothriocephalus). 

 The second is from Carcharhinus obscurus, and the third from Sphyrna tiburo. 



One of the most interesting finds recorded in this paper is the species of Rhine- 

 bothriwm, near R. flexilt Linton, found encysted on the viscera of the toad-fish 

 ( ( >jixiiniiK tun). These cysts, occurring as they usually do in (dusters (tie-. .Y.i), suggest 

 some habit of budding while in the blastocyst (plerocercus) stage. Nothing of this 

 kind, however, was demonstrated. Since this species appears to be very common in 

 the toad-fish of Beaufort, and toad-fish are abundant and easy to get. the form might 

 well repay a more extended study than is given it in this report. The same species 

 was found encysted in six hosts, including the toad-fish. 



Rhynchobothrium speciosum Linton was found for the first time in the adult 

 stage. The final host was Carcharhinus obscurus. Among the larval forms belonging 



