POLYPI. 535 



been described by Allman. (Report of British Association, 

 1844, Notices, p. 66.) Its tentacles are capitate, and arranged 

 in two series, and its internal structure is exactly the same as 

 that of Actinia. Coryne squamata, which was found on 

 Fucus in the Baltic, near Dantzic, has been described by 

 Rathke (Archiv, 1844, Bd. i, p. 155; or Annales d. Sc. Nat. 

 t. ii, 1844, p. 200), and found to be of distinct sexes; a 

 Coryne, also, found by Rathke on the coast of Norway, 

 agreed pretty nearly with the Dantzic species. A new 

 hydroid Zoophyte has been described by Quatrefages (Annales 

 d* Sc. Nat. t. xx, 1843, p. 230; and t. i, 1844, p. 11) as 

 Synhydra. This marine Polype, presents internally a true 

 horny polypidom, which supports two sorts of individuals, 

 the one sort is of a clavate form, and has no mouth, whilst 

 the other is of a saccular figure, and is furnished with an oral 

 aperture. The mouth in it, is placed upon a papilliform 

 eminence, the base of which is set round with numerous 

 tentacles. These tentacles vary in number (34 and 36) 

 according to the size of the individual, and are arranged in 

 two series, in groups together. The common base from 

 which these different Polypes pullulate, is very thin, and 

 forms a peculiar network. The intestinal cavities of the 

 individual Polypes communicate with each other by means of 

 canals which penetrate both the soft and horny substance of 

 the Polype. Quatrefages, who met with these Polypes on 

 the coast of Brittany and Normandy, affixed on various 

 univalve shells inhabited by Paguri, proposes for it the ap- 

 pellation of Synhydra parasita. The individuals without 

 mouth, subserve merely to propagation ; their free, expanded 

 extremity presents minute uneven elevations, which have a 

 cauliflower-like aspect, beneath which, oval bodies, as sexual 

 organs, project. Amongst these two forms of highly irritable 

 and contractile Polypes, a multitude of smaller Polypes, in 

 all stages of development, are seen project ing from the broad 

 polypidom. Van Bencden (Bulletin de 1' Academic Royale 

 de Bruxelles, t. xi, 1841, p. 305), who will not recognise the 

 Elentheria of Quatrefages as a distinct genus of Polypes ; 



