STAUROCALYPTUS PLEOEHAPHIDES. 223 



liptieal oscukim on one side of the npper end, 18 mm. b}^ 7 mm. 

 across. Thickness of wall in the middle, 8 mm. 



The third specimen again is attached to a large Hexadlnella 

 lorica (S. C. Isl. No. 448), together with Lanuginella pupa, Leu- 

 copsacus scoliodocus, etc. Locality, Outside Okinose by the Iwado- 

 line. Total height, 40 mm. Greatest breadth, 30 mm., the body 

 being nearly circular in cross-section. Thickness of wall in the 

 lower part, about 10 mm. The roundish osculum, 13 mm. in 

 diameter. 



The following are the details of the macroscopic characters 

 of all the three specimens taken together. 



The oscular margin is thin and simple-edged. By far the 

 greater part of the external surface is uneven on account of the 

 presence of numerous small conuli, lying at distances of 3-10 mm. 

 from one another. From each such conulus there spring a num- 

 ber of prostat spicules arranged in a loose divergent bunch. The 

 prostat bunch generally comprises both diactins and pentactins, 

 but sometimes consists of the latter alone. 



The diactinic prostals are generally strong needles of various 

 lengths. They may project to a length of 25 mm. or more, be- 

 ing directed on the whole obliquely outw^ards and upwards, though 

 there may exist some that proceed straight outwards or even 

 somewhat downwards. Those in the broadest part of the body 

 are the longest. The needles give an altogether spiny appearance 

 to the sponge. Seen under the hand-lens, some of them may 

 present a dirty brownish color due to a thin incrustation of some 

 foreio;n substance. Adhering to them are seen here and there 

 some animal remains, among which Foraminifera shells are the 

 more common. 



The pentactinic prostals are of a modeiately Inrge size. They 



