343 



seven to ben (but exceptionally sixteen) mm. apart at their summits. 

 Most of these ribs are simple and continuous, from the umbilical margin 

 on one side to that on the other, but they occasionally almost bifurcate 

 or trifurcate at or near the umbilical margin, and a few shorter ribs are 

 here and there intercalated between the longer ones, where one or more 

 faint and obscure minute riblets can also be detected. On each side of 

 this volution and especially near the aperture, some of the longer ribs are 

 strongly flattened downward at their summits, and widened, sometimes 

 for quite a long distance, longitudinally. On the inner wall of the 

 umbilicus all the ribs are obsolete, and its surface consequently is quite 

 smooth. 



Sutural line not well seen, but apparently very similar to that of 

 P. Otacodensis. 



The largest and best specimen known to the writer, the one figured, is 

 septate throughout, though most of the sutures are either coverrd by the 

 test, or so badly worn by exposure, that their finer details are completely 

 obliterated. Its dimensions are: maximum diameter, 191 millimetres 

 (or 7^ inches) ; greatest breadth, 75 mm. (or 3 inches) ; width of um- 

 bilicus, about 47^ mm. 



James Island, north of Victoria, V,I., Mr, Fred. Neeves, January, 1888: 

 the fine specimen figured, which has most of the test preserved and upon 

 which the preceding description was based. It was kindly lent to the 

 writer by the Natural History Society of British Columbia. 



A crushed and distorted but testiferous specimen, some three inches 

 and a half in its greatest diameter, collected by Mr. A. Raper in 1893 from 

 the Vancouver Co'al Company's No. 1 shaft, at Nanaimo, and presented 

 by him to the Provincial Museum at Victoria, is probably referable to 

 this species. Its outer volution is marked by about thirty narrow, 

 transverse but slightly flexuous, simple ribs, with broad flat spaces 

 between them. Some of these ribs extend to the umbilical margin, but 

 others not quite so far. 



Hornby Island, W. Harvey (1893, 1894 or 1895) : a well preserved 

 specimen, a little more than six inches in its greatest diameter, of a 

 variety of this species in which the ribs are nearly obsolete anteriorly, 

 the outer half of the last volution being almost or quite smooth. This 

 specimen is the property of the Provincial Museum at Victoria. 



Sucia Islands, J. Richardson, 1874 : a large and well preserved frag- 

 ment, consisting of about half of one volution, which is not quite four 

 inches and a half in length, by about two and a half in breadth. 



P. Neevesii, apparently, has much more numerous and more closely 

 disposed ribs than P. Otacodensis, and the outer volution of the former is 

 3^— M. F. 



