ON SOME JAPANESE CALCAREOUS SPONGES. 3 



of the projecting apical rays of gastral qiiadriracliates. Several of 

 the tubes are seen to bear diverticuluna of varying length, the 

 blind end of which is outwardly directed and may sometimes 

 show a perforation representing osculum at an early stage of 

 breaking through. The deeper parts of the colony give quite a 

 different view from the peripheral. The inner continuations of the 

 radial tubes branch and anastomose with one another and thus 

 form a complicated network of tubes which constitutes the greater 

 part of the mass of the colony. Here the diameter of the tubes 

 and the thickness of wall are somewhat greater than in more 

 peripheral parts of the colony. The sponge is colourless in alcoliol, 

 its texture rather firm and compact. 



The second specimen (Sei. Coll. Spec. No. 2) was also obtained 

 by K. AoKi at the same locahty. It is an irregularly shaped 

 mass, 80 mm. high, and 40 mm. in maximum diameter. The os- 

 cular tubes are on the whole of a larger calibre than those of the 

 type- specimen. They reach 14 mm. in length and 5 mm. in width 

 in the widest part, where the wall is nearly J mm. thick. The 

 dermal surface is relatively smooth, the tufts of oxea being not so 

 strongly developed as in the type- specimen. 



The third specimen (Sei. Coll. Spec. No. 3) was obtained by 

 Prof. Ijima at the same locahty. It is a small colony, provided 

 with about 30 oscular tubes. In external characters it agrees fairly 

 well with the type -specimen. 



The fourth specimen (Sei. Coll. Spec. No. 4) was collected by 

 Mr. K. Yendô at Öshima, in the Province of Shima. It is a little 

 smaller than the type- specimen. Height, 30 mm. Maximum dia- 

 meter, 65 mm. Minimum diameter, 40 mm. 



The fifth specimen (Sei. CoU. Spec. No. 5) hails from the 

 same locality as the preceding. It represents an irregularly 



