l6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 9I 



often have microscleres of more or less elaborate form. The gen- 

 eral architecture is plumose because of the smooth spicules echinating 

 the tracts or fibers. 



AXOCIELLA Kallmann 

 AXOCIELLA CALLA, n. sp. 



Holotype. — U.S.N.M. no 22333 > from station 45, latitude 18° 13' 

 10" N., longitude 67°25'3o" W. to latitude i8°i4'3o" N., longitude 

 67°25'3o" W., February 13, 1933, 20 to 40 fathoms. 



This specimen looks like a cylindrical sponge, but actually it is 

 encrusted on a gorgonian stem. It reaches a diameter of 15 mm; one 

 portion is 11 cm long and another is 16 cm long, on the same basal 

 gorgonian. As preserved in alcohol the color is a medium gray (the 

 label bears a notation that there is a color sketch), and the consistency 

 is spongy. The external surface is porous, or even cavernous. It is 

 possible that the sponge had died before collection and was partially 

 macerated, but the histological condition is not such as to make this 

 certain. Because of this porous or almost honeycomb structure, the 

 oscules and pores are atypical. The gross chambers continue on down 

 into the endosome, being frequently about i mm in diameter. Between 

 them there are ascending tracts containing spongin and ranging from 

 60 [JL to 140 /x in diameter. In these the spicules are arranged in such 

 an axinellid or plumose fashion that nearly all could be said to be 

 echinating rather than coring. These megascleres are monaxons that 

 range from plain styles to subtylostyles and have average dimensions 

 of about 10 fji by 150 /a, but the range in size is considerable. The 

 microscleres include abundant palmate isochelas about 20 fi long and 

 toxas only once bent, the distal extremities being practically straight ; 

 these range from 40^1 to 130 /a in total length. 



It is difficult to discuss the relationships of this species because, 

 although no sponges at present referred to the genus Axociella are 

 close to it, the genus has been generally overlooked, and it is quite 

 likely that a careful search (especially a study of original specimens) 

 will disclose that many species now referred to other genera should 

 be transferred to Axociella. Some of these may prove to be closely 

 related to the West Indian form A. calla. The cavernous structure, 

 however, is seldom associated with species having isochelas as com- 

 pared to anisochelas, for which latter see the genus Mycale Gray. 

 Another genus to be noted in this regard is Thalysias Duchassaing de 

 Fonbressin and Michelotti, of which the genotype should be fixed as T. 

 virgultosa D. & M. (1864, p. 86) (they regard this as identical with 

 Spongia virgultosa Lamarck, 1813,'p. 446, but this is doubtful). 

 Thalysias differs from Axociella in having spiny echinating spicules. 



