154 ART. 7. T. IJIMA : IIEXACTINELLTDA, IV. 



which 18 much too rare and inconstant to be counted amons; the 

 regular hexasters of the species, may be said to be in appearance 

 not unlike the macrodiscohexaster of Aulosaccus ijimai F. E. 

 ScH.; it is apparantly in the state of nearest approach to the 

 (liscoctaster, into which it may l)ecome converted by comparatively 

 short steps of change. 



Micro(l(!^cohexasiers (PL XII., fig. 26) of only 1-3-25/-'- diameter 

 and of the usual appearance are common in both the dermal and 

 gastral membranes as well as in the subdermal and subgastral 

 trabecul^e. In some individuals they are much more abundant 

 than in others. In the choanosome they do not seem to occur. 

 In stained pi'eparations a nucleus — in all probability representing 

 a silicoblast — is almost always seen in each of the angles formed 

 by the principals, as shown in PL XL, fig. 18. The interspaces 

 between the exceedingly delicate terminals are filled up by a 

 protoplasmic matrix, so that the entire rosette first attracts one's 

 attention as a small, faintly colored mass of spherical shape. 



Soft Parts. 



8ome fragments fixed and ])reserved by myself at different 

 times at the place of capture have been utilized-for making the 

 following observations on the soft parts. 



The chambers are so numerous and densely crowded together 

 that it is difficult to exactly determine the shape and extent of 

 each (see PL XL, fig. 22). However there can be no doubt of 

 their being as usual cup-like or thimble-like in shape. The 



