MARINE POLYZOA. 7 



2. CATENICELLA VENTRICOSA. PL II. figs. 1, 2; PI. III. 

 figs. 1, 2, 3, 4, 5. 



Cells oval, compressed. Avicularia wide, supporting sometimes 

 a cuplike cavity, sometimes a closed, broad, conical spine. 

 Fenestrae 7, with fissures radiating towards a rounded central 

 pore. Front of cell studded with minute acuminate papillae ; 

 back smooth, sometimes spotted. 



Catenicella ventricosa, Busk, in Voy. ofRattlesn. i. 357- 1. 1. fig. 1 . 

 Hab. Bass' Strait, 45 fathoms. 



Colour dirty white or brown ; habit stiff; stem strong, straight ; 

 branches short and crowded ; probably attains a height of 4 or 5 

 inches. The only other species with which it can be confounded 

 is C. amphora, from which it differs in the greater size and more 

 irregular form of the lateral processes ; in the presence of the mi- 

 nute papillae on the surface ; and in the absence of the narrow lon- 

 gitudinal band on the back ; instead of which, the older cells in 

 C. ventricosa exhibit a sort of broad scutum, almost covering the 

 back of the cell, and sending off two lateral bands on the sides 

 of the cell, one passing below the avicularium and above the late- 

 ral area, and the other towards the acuminated apex of the avi- 

 cularium. It also w r ants the raised bands which in C. amphora 

 pass from the sides of the mouth to the apex of the avicularium 

 in front. One large specimen presents a variety worthy of 

 note : in this the backs of all the cells, except one here and 

 there, exhibit (internally?) numerous irregular- sized leopard-like 

 spots. 



3. CATENICELLA HASTATA. PI. II. figs. 3, 4. 



Cells oval. Fenestrae 7-9, disposed in a crescent, with fissures 

 radiating towards the median line. Avicularia supporting large, 

 pyramidal, pointed, hollow processes, compressed, and perforated, 

 before and behind, by five or six small circular pores. 



Catenicella hastata, Busk, in Voy. of Rattlesn. i. 355. 

 C. bicuspis? Gray, Dieffenbach's New Zealand, ii. 293. 

 Hab. Bass' Strait, 45 fathoms. New Zealand. 



Of a yellowish white colour, sometimes reddish. Forms fine 

 bushy tufts, with long wavy branches, arising from a short com- 

 mon stem, and attaining a height of 5 or 6 inches. It appears 

 sometimes to be parasitic upon other Polyzoa, and is then much 

 smaller. Its peculiar characteristics are, the perforated and stri- 

 ated scutiform area on the front of the cell, and the perforated 

 or apparently perforated pyramidal lateral processes above each 

 avicularium. 



