273 



lu addition to these raegascleres the parenchyme of Cydonium 

 gigas coütains au amouut of various asters. 



Spiculea. Orihotriaene. Stout, the rhabdome long, straight, 

 sharp-poiuted. The cladi are not very long , curved , seldora ab- 

 ruptly beut. 



Aiiatriaene. There are two distiuct kinds. The long, slender 

 pareuchymal anatriaenes are varying in size and shape, especially 

 with regard to the cladome. In some specimens they are remar- 

 kably rare, but always present. The minute anatriaenes occur, as 

 is stated above in the dermis. 



Protriaene. Rare; very long and slender. 



Oxea. Abundant, varying in length and diameter. They are 

 generally somewhat curved , and always shorter than the triaenes, 



Styli occur in several specimens, but I do not believe them to 

 be of any specific value. 



Microxea. Abundant in the dermis, hispidating. 



Sterraster. The difference of the long and short diameter of 

 the ellipsoid is but small. 



Oxyaster, Varying considerably in size. The actines are few , 

 long , generally conical , sometimes subcyliudrical , and as a rule 

 subspined. The spines can only be seen with a high power. Trans- 

 itious are found to plesiasters and pycnasters. They occur chiefly 

 in the parenchyme , but a few are seen in the cortex. 



Chiaster. Sometimes knobbed. They often line a portion of a 

 canal, but never so markedly as they do the external surface, 



Found near Posillipo and Nisida; 30 — 50 meter. 



Isops mac ulosus n.sp. 



The shape of Isops maculosus is spherical, sometimes quite 

 regularly globular, sometimes more ellipsoid or oviform. Procts 

 and stoma's are scattered over the surface without any order ; 

 the former are rather large. No spicules project beyond the cortex 

 and thus is the sponge smooth on the touch. The size is from 

 2X2 to 4X8 cm. in diameter. The colour is dirty pale buff 

 with irregular sepia-coloured spots of various tints. 



