14 ART. 9. — I. IJIMA I HEXACTINELLIDA. 



of ray 6-16 /a Occasionally I have found this peculiar spicule 

 adhering to the shaft of the dermalia. 



In details of character all the spicules thus far noticed agree 

 with the corresponding elements in Corbitella speciosa ; so that, 

 what I have said concerning them may be considered to hold 

 good here also. 



Sword-shaped hexactins of variable size, which by the manner 

 of their arrangement distinctly prove themselves to be the dermalia, 

 are plentifully represented in my preparations (PI., figs. 14 and 

 15). They have mostly strong rays, measuring 20 /* or more — 

 up to 27 /* — in breadth near the central node, while in other and 

 weakly developed cases the breadth may not exceed 8 ,«. The 

 total length of the spicule may reach nearly 1 mm. The hilt-ray, 

 up to 200 !*■ in length, narrows but slightly towards the rounded 

 outer end ; it is nearly or quite smooth throughout. In certain 

 cases I have seen that ray reduced to a knob ; and in some others 

 it was the blade-ray that was so unusually shortened as to differ 

 not much in length from the paratangential rays. Whether the 

 much thicker rays of average dermalia can be looked upon as one 

 of the distinguishing characters of the species in contrast with 

 Corbitella speciosa, will require testing with more specimens. 



The gastralia are not represented in my preparations. 



As regards the hexasters, the occurrence of graphiocomes is 

 certain, since the rhaphides (145,« long) are not uncommonly 

 met with, either scattered or grouped into bundles. 



The floricome measures 98-114/^ in diameter. It is therefore 

 considerably larger than in Corbitella speciosa (72-83 ,«). Each 

 slender principal bears a perianth of 6-8 terminals. Terminal 

 plate with 5 or 6, moderately large claws. 



A difference much more remarkable than that in the size 



