284 TORRE Y. [VOL. II. 



Cori has discussed in an interesting fashion all save the last 

 four species. Roule's P. Sabatieri and Andrews' P. arcJiitecta 

 were apparently unknown to him, though descriptions of both 

 were published before the date of his manuscript. P. Sabatieri 

 is known to me only through a meager description. It differs 

 from the other European forms in size and habit, and approaches 

 P. architecta in these respects. The latter possesses the simple 

 lophophore and comparatively small number of tentacles (60) 

 of the European species. It may be distinguished from them 

 (with the exception of P. Sabatieri, with which it may prove 

 identical) by its larger size, its straight tubes and solitary habit, 

 its strong longitudinal muscles (excepting P. psammophila}, the 

 presence of a ciliated groove in the digestive tract, and possibly 

 by a separation of the sexes. While it agrees fairly well with 

 P. Buskii in size, it differs from that species m the other char- 

 acters enumerated, as well as in the complexity of the lopho- 

 phore and the number of tentacles. It is thus more closely 

 allied to the European than to the Australian and Philippine 

 forms. 



The differences between P. australis and P. Buskii are merely 

 of habit and size, which has caused Benham to suggest their 

 identity on the supposition that these differences are due to 

 dissimilar environmental conditions. 



The description of the Japanese species has been inaccessible, 

 so that I can state nothing with regard to it save its existence. 



It is an interesting fact that no one has cared to segregate 

 the species of Phoronis under more than one generic name, and 

 indicates the trifling character of the differences which serve to 

 distinguish them. We may separate them, however, into two 

 groups widely separated geographically. In the one belong the 

 European forms, including, perhaps, the American P. architecta. 

 In the other belong P. australis and P. Buskii. We may dis- 

 regard the Japanese species on account of dearth of information, 

 and the P. psammophila which Haswell has found at Port Jack- 

 son and which may have been brought from the Mediterranean 

 on a ship's bottom. 



P. pacifica occupies a place intermediate between these two 

 groups both geographically and anatomically, but is somewhat 



