GYMNOEHYNCHUS HORKIDTJS. 401 



VIIL— ON GYMNOEHYNCHUS HOEETPUS, A NEW 

 CESTOID ENTOZOON.* (Plate VI. p. 445, vol. ii.) 



The genus Gyninorhynclms was instituted by Eudolphi, for 

 the reception of a worm which infests the muscular tissue of 

 the Brama Raji, and which had been placed by Cuvier in the 

 genus Scolex. This worm, Gymnorhynchus rcptans (Eudolphi), 

 Scolex gigas (Cuvier), is the only species which has been 

 hitherto observed. It is described by Eudolphi, Cuvier, 

 Blainville, and Milne Edwards, and figured by Bremser. 

 The characters of this genus, according to Eudolphi, are : — 

 Body depressed, continuous, very long, with a subglobose 

 cervical receptacle ; head provided with two bipartite 

 suckers, and emitting four naked retractile proboscides. 

 Bremser, however, represents in his atlas the four proboscides 

 not as naked, but as armed with recurved hooks, an arrange- 

 ment which can only be recognised when they are fully 

 extended. Milne Edwards, in the last edition of Lamarck's 

 Invertebrate Animals, has defined the genus thus: — Body 

 depressed, continuous, or without articulations, composed of 

 three parts ; one median, subglobose, prolonged backwards 

 into a very long tail, and forwards into a wrinkled neck ; the 

 cephalic bulging provided with two bipartite suckers and 

 tour papillose tentacula. 



When dissecting the, sun-fish, which formed the subject of 

 a former communication to the Society, 1 found in the liver 

 a number of entozoa which presented arvery curious appear- 



■ Read before the Wernerian Natural History Society, Kcln-uan 2o, lsii. 

 [Dr. Cobbold, in bis Treatise oil the Entozoa places iliis parasite amongst 

 tin- Tetrwrhynchidee, and names ii Tetrarhynch/us reptims. —Eds.] 



