240 JMiss Jane Stephens on 



recurvecl points. Lengtli 0'08-0*13 mm., with a maximum 

 thickness o£ about 0'0025 mm. ; (b) with very long and very 

 slender straight arm?, and with rather an abrupt curve in 

 the middle of the spicule. The maximum length is about 

 0-8 mm. 



The sponge was dredged off the west coast of Ireland in 

 388 fathoms. 



Eiirypon ienuissimum, sp. n. 



The sponge is growing in a small, very thin encrustation on 

 coral. 



The main skeleton consists of acanthostyli which are set 

 vertically with their heads on the substratum. The dermal 

 skeleton consists of styli, apparently arranged in bundles, 

 set vertically to, and projecting above, the surface, but their 

 exact arrangement could not be made out owing to the scanty 

 material available for examination. 



Spicules. — (1) Acanthostyli. The largest of these spicules 

 are from 1 to 1"5 mm. in loigth, with a maximum diameter 

 of 0*021 mm. The slightly curved shaft tapers to a rather 

 short point at the apex. The base is covered, sometimes 

 very sparingly, with rather short blunt spines. Smaller 

 acanthostyli, spined to some distance along the shaft, are 

 intermediate both in size and in amount of spination between 

 the foregoing and the smallest acanthostyli, which are about 

 0'12-0'14 mm. in length. These latter are thickly spined 

 along their whole length. The head is covered with sliort 

 blunt spines, the shaft with recurved spines. (2) The 

 dermal styli are minutely spined on the head ; they are 

 O-45-0-7 mm. by O'OOG mm. (3) Isochela palniata?, 0-021 

 mm. in length, (4) Toxa, very slender, with long straight 

 arms. Maximum length about 0'55 mm. 



The sponge was dredged off the west coast of Ireland in 

 388 fathoms. 



Eurypon microchela, sp. n. 



The sponge is growing in a very thin encrustation on 

 coral. 



The main skeleton consists of acanthostyli, which are 

 placed very close together and are set vertically with their 

 heads on the substratum. The long acanthostyli project far 

 above the surface of the sponge. Tlie dermal spicules are 

 in small bundles and project more or less obliquely above the 

 surface. 



