152 Transactions of the South African Philosophical Society. 



individuals, one in a large limestone rock which had been for some 

 months out of water before being used to form part of the rock-work 

 in the tank, three in a small piece of stone at the further end of the 

 same tank introduced later, and a solitary specimen in another tank. 

 Further evidence was afforded by the fact that a dried piece of lime- 

 stone put into the tank for the purpose of confirmation had at least 

 one Phoronis on it about eight months afterwards. 



During the examination of the specimens in the limestone a single 

 specimen (A) was observed which appeared to be a different species, 

 being larger, of a somewhat different form, and pigmented. This 

 was the only one of its kind then found, and special care was taken 

 to observe its habits and behaviour in the living condition before 

 preserving it for more detailed examination. It appeared to be 

 thriving and specially active, and it was disappointing to find, on 

 proceeding to examine it again, that this unique specimen had 

 entirely disappeared, leaving only the end of the tube visible. 

 After a time, however, the headless trunk of the animal was slowly 

 protruded, and a month later the head region had apparently grown 

 to its former dimensions. Fig. 2 is from a photograph of the animal 

 at this time. 



Only two other specimens (B and C) of this species have as yet 

 been procured, but it will probably be found that the animal is not 

 so rare as would seem to be indicated. 



With regard to the first species (Phoronis capensis, sp. n.), there is 

 little of special interest ; but as the specimens, on account of their 

 hardiness and their thriving so well in captivity in spite of somewhat 

 severe handling, afforded excellent material for observation of their 

 habits and certain features of the living animal, an opportunity was 

 taken to add a few details to the little that is known on these points. 

 Fig. 1 represents one of this species carrying eggs, and is from the 

 living animal. 



The second species is of more interest structurally. It shows 

 an apparent advance on species hitherto described in the circum- 

 cesophageal nerve ring being partially sunk in an involution of the 

 epithelium of the body, the single nerve chord being well developed, 

 the nephridia somewhat modified, the longitudinal muscles of the 

 body increased in number, and ova deposited in gelatinous mass 

 in the tube instead of in the tentacles. 



These distinctive features, especially the first, seemed to neces- 

 sitate the separation of this form from others as a new genus — 

 Phoronopsis. 



The following description of this animal is necessarily somewhat 

 incomplete on account of the limited material available, but I hope 



