Miscellaneous. 147 



birds, especially the smaller ones, harbour a multitude of Helmintha, 

 which are easy to procure, and which I have been able to examine 

 while alive. Their study, from the point of view of habitat, has 

 already furnished me with a great mass of facts which fully confirm 

 the general considerations of my preceding note. 



I will first cite three species of Nematoids : — Ascaris spiculigera, 

 Kudolphi ; Ascaris heteroura, Creplin ; and Spiroptera aculeata, 

 Creplin. Ascaris spiculigera was found by Creplin in the digestive 

 tube of the guillemot (Uria troile) ; and it is there also that I have 

 myself met with it at Itoscoff ; but it has been noticed in many 

 other sea-birds (divers, grebes, mergansers, auks, sea-gulls, pelicans, 

 cormorants). The Ascaris heteroura is not uncommon in the intestine 

 of the golden plover. As for Spiroptera aculeata, it is found abun- 

 dantly in the proven triculus of the variable sandpiper. 



The Ecliinorhynchi are very irregular in their habitat, but they 

 are also unfortunately very difficult to characterize. The sanderling 

 (Calidris armaria) and the common turnstone (Strepsilas interpres), 

 in which no species of Acanthocephala were previously known, 

 have furnished me with two probably new species. That of the 

 sandeiiing has an oval body, very much swollen and regularly folded 

 across ; that of the turnstone is distinguished, on the contrary, by 

 a very long linear body armed with prickles on its anterior parts, 

 and by a very short trunk. A species allied to the latter, but still 

 more elongated, inhabits the intestine of the laughing-gull ; it is 

 perhaps Echinorhynchus linearis, Westrumb. I have often obtained 

 Echinorhynchus injiatus, Creplin, in the ringed plover, and in the 

 variable sandpiper Echinorhynchus polymorphus, Bremser, which is 

 very common in ducks. On the other hand, Echinorhynchus striatus, 

 Goeze, which usually lives in the intestines of waders, and par- 

 ticularly in those of the heron, is found at Roscoff in a totipalm 

 Palmipede, the common cormorant. This Echinorhynchus, of which 

 we possess as yet only two bad specimens, is distinguished from all 

 its congeners by its strange forms and its mode of fixure. The 

 anterior part of its body, which is very much inflated and covered 

 with prickles, becomes, when the trunk is retracted, a true sucking- 

 disk, by the aid of which it fixes itself to the walls of the intestine. 

 In this state it resembles certain spinous Distomata, such as the 

 Distoma ferox, Zeder, which likewise inhabits the intestine of the 

 herons, and with which one might at first sight confound it. 



The Cestoids are also numerous, and not less interesting. The 

 species belonging to the genus Tcenia may be divided into two groups, 

 plainly distinguished by the relative size of the hooks with which 

 their trunk is armed. Tcenia crassirostris, Krabbe, and Taenia filum, 

 Goeze, have the hooks very short, and are therefore easy to distinguish. 

 The first is found in the ringed plover, the second in the variable 

 sandpiper. The species with large hooks are less distinct and less 

 easy to recognize. Tcenia retirostris, Krabbe, lives in the intestine 

 of the common turnstone ; Tenia nymphcea, Schrank, a form very 

 nearly allied to the preceding, is peculiar to the curlew ; the Tcenia 

 ericetorum, Krabbe, is only found in the golden plover ; Tcenia 



