32 THE OCEANIC HYDROZOA. 



Length of the inferior nectocalyx . . 1 inch. 



Depth „ „ . • 5 .. 



Thickness „ „ . . i-, „ 



Ca3nosarc, between two and three inches long. 



Polypite, i inch. 



Sacculus of the tentacle, ~ inch. 



The three specimens on which this description is founded were taken on the 15th of 

 July, 1847, in the Southern Pacific Ocean, in lat. 36° 31' south, and about fourteen miles from 

 the eastern coast of Australia. One was quite colourless, except the sacculi of the tentacles, 

 which had the usual reddish hue. In the other two the nectosacs were irregularly stained 

 with red. 



I took several specimens of what I believe to be this species once again, on the eastern 

 coast of Australia (December 21st, 1848). At least, the only difference I could detect was 

 the absence of the median division of the transverse plate which forms the anterior boundary 

 of the hydrcecium in the superior nectocalyx. In the largest of these specimens the 

 superior nectocalyx was even thicker and blunter than in the figured specimen ; while the 

 smaller forms showed insensible gradations to such a figure as that represented in 1 d. 

 It will be observed, however, that this young specimen has the characteristic somatocyst and 

 tubular cEEcum of the nectosac. Tiie detached superior nectocalyces of young specimens of 

 the same species were taken in the South Atlantic and in the Indian Ocean. 



MM. Quoy and Gaimard, took D. dispar in the Straits of Gibraltar, but it is not 

 noted by the German investigators of the Mediterranean Caliicoplioridce, unless, as I am 

 inclined to think, it is identical with Gegenbaur's B. tiirgida. 



I have taken some pains to unravel the history of this, the first discovered of the 

 Calycophorida, and to trace its identity through the manifold changes of name which it has 

 undergone. It is described in tlie following words by its original observer, Bory de 

 St. Vincent : 



"■Salpa (bipartita) lanceolata bipartita. — Le Biphore biparti est si transparent qu'on ne le 

 distingue pas dans I'eau ; lorsqu'on Ten tire, il a I'air d'une lame de crista!, et ne presente 

 aucune sorte d'organisation. Son corps est oblong, et comprime lateralement. La partie 

 anterieure presente cinq angles saillans ; le cote dorsal etant carene, I'inferieur est 

 au contraire sillonne. On reconnait dans cette partie deux cavites longitudinales ; de 

 la supericure sort un filet, souvent tres-long et rarement entier ; il supporte, quand il 

 existe, une foule de petits corps qui ressemblent aux glandes pedicellees de plusieurs 

 vegetaux. La partie postcrieure est amincie a son extremite, et a quelqucs rapports avec la 

 forme du fer d'une lancette ; le cote superieur, qui est plat, est cpais d'une ligne et demie. 

 Dans cette cpaisseur se trouve une cavite interne, dans laquelle entre une sorte d'eperon 

 qui termine la partie anterieure ; et c'est la toute I'union apparente de deux parties de 

 I'animal. II y a aussi une autre cavite inferieure dans la moitie de derriere, dont I'ouverture 

 echancree au point de jonction des deux parties, forme un cran a leur union."* 



' Bory de St. Vincent, ' Voyage dans les quatre principales lies des Mers d'Afrique,' 1804, t. i, 

 pp. 134, 135, note ; and ' Collection de Planches,' pi. vi, fig. 3 a, b, c. 



