NO. 3593 VICTORELLA — BANTA 9 



the former, it is at the junction of the cardium and the caecum. Un- 

 fortunately, it is difficult to delimit the cardiac stomach in Victorella 

 argilla because a cardiac valve is lacking in this species. Neverthe- 

 less, it is clear that the greater part of the distal digestive tract 

 proximal to the vacuolated cells of the esophagus is invested in very 

 fine concentric muscles that may become elaborated into well-defined 

 sphincter muscles at three possible sites. Figure 5 shows a polyp 

 with all three sphincters developed though, as a rule, only one or two 

 bands are present at a time. There is no trace of a gizzard or other 

 chitinous reinforcement of the distal digestive tract. 



Reproductive system. — Both form A and form B individuals 

 have been found to contain ripe testes and ovaries. Both gonads 

 occur in the distal region of the zoecium of form B, but they are 

 located more proximally in form A. An intertentacular organ is 

 present in most of the form B individuals examined, but I have not 

 observed any in form A. 



One of Braem's (1951, p. 33) reasons for separating Tanganella 

 from Victorella was the possession of an intertentacular organ by the 

 latter (Victorella) but not by the former {Tanganella). Sexually 

 mature Tanganella extrude their eggs through a supraneural pore 

 (Braem, 1951, p. 27; see also his discussion of T. mulleri on p. 6). 



Unfortunately, none of the material at my disposal contains em- 

 bryos and there is no sign of a modification of the vestibular wall to 

 indicate that brooding takes place there as it does in Tanganella 

 mulleri (Braem, 1951, p. 27). The extensive mass of foreign material 

 filling the vestibule indicates that if indeed eggs are brooded in this 

 species, the brooding must ahiiost certainly take place elsewhere — 

 in the tentacle sheath, for example. 



Ecology 



The mature colony of form B is typically a thick, sandy or argil- 

 laceous carpet growing in sheets or knobs over hard substrate. The 

 well-developed colony is by no means easily recognized as a polyzoan 

 because of the massive accumulation of detritus and sediment between 

 the zoecia. When the lophophores are retracted, foreign material 

 effectively obscures the apertures, so that, even under high magnifi- 

 cation, the colony is easily disregarded as inorganic. Teasing apart 

 the zoarium fails to yield any information because the zoecia and 

 connecting tubules form a tightly integrated mass, and zoecia tend 

 to tear open rather than separate, with the result that the fragile 

 polypides are lost against a background of sediment. 



Victorella argilla, nevertheless, is quite abundant. It has been 

 recorded from seven localities from Tomales Bay to Imperial Beach 



233-804—67 2 



