74 U.S. NATIONAL MUSEUM BULLETIN 272 



of spongiii always insigniiicant. Consistency of live sponge soft, 

 texture loose. 



Megascleres feebly curved to almost straight fusiform amphioxea, 

 sharply pointed at their tips, and entirely smooth; length range 240- 

 330 n, width range 10-12 /x. 



True microscleres absent; however, immature and slender gem- 

 moscleres often abundant in dermal membrane, also occm"ring in 

 isolated batches in inner sym plasm. 



Gemmoscleres typically often distinctly curved, rarely straight, 

 cylindrical amphistrongyla, sometimes bearing a single terminal 

 spine in the prolongation of their axis, thus resembling am.phioxea; 

 their shaft abundantly spined, spines erect and often subdivided 

 in the central portion of the scleres, progressively recurving towards 

 their extremities; length range 72-110 n, width range 2-4 /x. 



Gemmules numerous in mature sponge, abundantly produced 

 even in smaU specimens, spherical, ranging in diameter 420-590 ju; 

 pneumatic coat well developed and unusually thick, consisting of 

 minute spherical air spaces; gemmoscleres embedded in this coat 

 in two distinct layers, i.e., (1) more or less radially arranged, arising 

 from inner gemmular membrane, often crossing each other at various 

 angles, and not reaching to outer gemmidar membrane; and (2) 

 lying on top of the first, more or less tangentially arranged, embedded 

 with their proximal portions in the pneumatic coat, their distal ends 

 protruding through outer gemmular membrane; foramen distinctly 

 tubular, porus tube slender and straight, always at least reaching 

 to level of pneumatic coat. 



Distribution. — Apparently widely distributed in tropical and 

 subtropical regions of Africa, the Indo-Pakistani subcontinent, and 

 Indonesia, ranging to the Philippines and New Guinea, as well as 

 through China to the U.S.S.R., and perhaps also to parts of south- 

 eastern Europe (Schroder, 1942). 



Color in life. — Ranging from yellowish gray to dark green. 



Discussion. — In view of the clear and sufficient description of 

 S. cerebellaia by Bowerbank (1863) and a number of subsequent 

 authors, it is difficult to understand why this species became relegated 

 to a most dubious position by the revising efforts of later workers. 

 Weltner (1895) recorded it from Africa under the name of S. hiseriata, 

 not realizing its identity with S. cerebellaia, and Annandale (1907b, 

 c, 1909b, 1916) described another four species without being aware 

 of the obvious affinities to each other as well as to Bowerbank's 

 species. However, more serious taxonomic confusions were yet to 

 come. The often abundant presence of immature gemmoscleres in 

 the dermal membrane and inner symplasm of some of these additional 

 "species" has led to the description of true microscleres in these 



