Notices of Irish Entozoa. 657 



armed Bothriocephalic The same phenomenon appeared in 

 several others. 



I made no farther observations respecting this anomalous 

 production till nearly a month afterwards, when, on the 2nd 

 of October, I examined a white sacculated tumor taken from 

 the outer surface of the stomach of a blockan, or young coal 

 fish, [Merlangus carbonarius). The outer covering of the 

 sac was composed of a very delicate, loose layer of peritone- 

 um ; under this was a much thicker and firmer, but transpa- 

 rent membranous capsule, entirely surrounding a very white 

 substance, apparently solid. On tearing open this second co- 

 vering, the enclosed Entozoon was dislodged by the slightest 

 pressure ; and on farther examination I found it to be pre- 

 cisely the same as that which formed the broad, flat division 

 of the compound animal in the intestine of the turbot. The 

 remarks I wrote down at the time are as follow. 



" Pure white, solid, opaque ; proboscis when fully exserted, 

 obcordate, and beset with numerous very fine bristles, which 

 I believe clothe its whole surface; bristles long and subulate : 

 • — the proboscis is moved by eversion and inversion alone. — 

 On tearing the animal to pieces, after being killed by a drop 

 of alcohol, I could see nothing like ova, but one of the frag- 

 ments exhibited four cords, which seemed to be of the same 

 nature as the rostella of Anthocephalus paradoxus" 



Two days afterwards (October 4th) I examined a similar 

 tumor, from the stomach of a blockan also. When dislodged 

 from its sac, the Entozoon was of the size marked a, Fig. 32 ; 

 in colour, proboscis, and everything else, it exactly resembled 

 the last. I cut it across through the middle, and with some 

 trouble extricated from the caudal end a distinct, living indi- 

 vidual, in all respects similar to the bothriated portion of the 

 compound animal seen in the turbot. Its four bothria were 

 in constant motion, giving the head that polymorphous ap- 

 pearance which is so remarkable in many of the bothriated 

 Certoidea. 



After examining the specimen for some time, I applied re- 

 peated drops of fresh water with a hair pencil, and soon had 

 the satisfaction of seeing it protrude four long, beautiful, crys- 

 talline rostella, armed with very numerous retorted hooks. — 

 A second tumor examined in like manner exhibited the same 

 appearances ; and in both, the obcordate proboscis of the op- 

 posite separated end, continued its motions as before the di- 

 vision. Two other tumors from the stomach of another fish 

 of the same kind exhibited exactly similar appearances. 



I next, on the 7th of October, compressed a specimen freed 

 from its envelopes, between two slips of glass, and on apply- 



