96 MARINE POLYZOA. 



represented in PI. LXV. fig. 2, has hitherto been known only in 

 certain fossil forms, the composition of which, as is observed by 

 M. -Edwards (Lamarck, Hist. d. An. s. Vert. ed. 2. ii. 193), is 

 " essentially the same as that of the SalicornaricB of Cuvier : " 

 but he goes on to say, " as only very minute fragments of them 

 have been found, it is unknown whether the cylinders resulting 

 from the coalescence of a certain number of longitudinal rows of 

 cells are articulated or not ; in the latter case the proposed 

 generic division should be retained, whilst in the opposite there 

 would be no sufficient reason to separate them from Cellaria 

 (Salicornaria} properly so called. 



The occurrence of a recent species clears up this point, if it 

 were not sufficiently evident before, and I am therefore so far 

 supported, in the distinction of the group from the Salicorna- 

 riadcB. The same value appears to be attached to this character 

 also by Hagenow (I. c. p. 59) ; and from a note in page 60 it 

 would appear that Prof. Philippi is now of the same opinion. 



1. VlNCULARIA. 



Branches of polyzoarium not tubular ; front of cells surrounded 

 by a raised border, arcuate above, nearly straight below. Ovi- 

 cells immersed, opening above the mouth of the cell upon which 

 they are placed. 



).. VlNCULARIA ORNATA. PI. LXV. fig. 2. 



Margin of cell much raised, granular ; lamina granular, irre- 

 gularly denticulate on its internal edge. 



Hob. Patagonia, Darwin. 



It would appear that the present species belongs more to the 

 type common in the cretaceous formation than to that met with 

 in the tertiary ; that is, to those Vincularice in which the cells 

 are surrounded with a border; whilst, according to Hagenow 

 (/. c. p. 60) and Reuss, the forms probably referable to the same 

 family group, though perhaps not to the same genus, the species 

 with ventricose, oval cells, e. g, (Cell, duplicata, labrosa, Miche- 

 lini, coronata, Schreibersi, fyc., Reuss, /. c.), are peculiar to tfye 

 tertiary rocks. This observation, however, will hardly hold good 

 with respect to such forms as Cell, macrostoma, Reuss, /. c. pi. 8. 

 figs. 5, 6; Cell. Haidingeri, pi. 7. fig. 30; Cell, cucullata, pi. 7. 

 fig. 31 ; Cell, escarata, pi. 7. fig. 32 ; all of which appear to me to 

 belong to the true Vincularia. 



The proper comparison, however, not only of these, but of all 

 fossil forms of Polyzoa, with recent ones, yet remains to be made. 



