NO. 17 NEW SPONGES— DE LAUBENFELS 5 



ally small, being only 15 /a or 16 /x in diameter. The megascleres com- 

 prise oxeas and orthotriaenes, the latter with rhabd diameter up 

 to about 20 fj. and length considerably over i mm. The oxeas are of 

 similar proportion ; their ratio toward the triaenes varies greatly, some- 

 times one and sometimes the other being more abundant. Anatriaenes 

 are rare, but when they do occur they are characterized by a peculiar 

 angular bend in each clad, instead of the ordinary symmetrical curve. 

 In the type specimen there are numerous triaenes in which the clads 

 are so reduced that each is merely a rounded lump at that end of 

 the spicule. The microscleres are distinctive and exceedingly abun- 

 dant, especially in the ectosome. They are minutely spiny or lumpy 

 microrhabds only i /x thick and seldom more than 5 fi long, but a few 

 are as much as 8 /a. 



Occasionally one sees, not in boiled-out spicule mounts but in sec- 

 tions of the sponge flesh, what at first appear to be asters. They are 

 usually irregular in shape, but once in a while they are nearly circular 

 in outline, 18 fx. in diameter. They may be rosettelike aggregations of 

 the acanthorhabds comparable to the grouping of anisochelas found 

 in such genera as Mycale; again, they may be mere clusters of crys- 

 tals precipitated by the preservation of the specimen. They are men- 

 tioned to indicate the difficulties involved in deciding whether a species 

 contains asters. 



The microsclere spiculation of this sponge is so distinctive that it 

 is difficult to cite close comparisons with other species. 



NEOTHENEA, n. gen. 



This genus, like Hezek'ia, is remarkable for lack of euasters. But 

 for this character it may be compared to Thenea Gray. The mega- 

 scleres are dichotriaenes, large and smaller oxeas, metasters, and bent 

 microrhabds that may be reduced asters. 



Genotype. — Neothenea enae, new species. 



NEOTHENEA ENAE, n. sp. 



Holotype.— U.S.N. M. no. 22321; from station t^j, latitude i8°i3' 

 50" N., longitude 67°39'2o" W. to latitude i8°ii'55"N., longitude 

 67°42'5o" W., February 10, 1933, 160 to 200 fathoms. 



This specimen is a mass 2 by 6 by 7 cm, apparently broken of¥ from 

 a much larger original flabellate structure, though the original external 

 form must be merely hypothetical. The color is whitish in alcohol, 

 and the consistency is mediocre. The surface is hispid, almost felt- 

 like, shaggy. There is a distinct cortex, a little over 500 ju, thick. There 



