ART. 12 HEXACTINELLID SPONGES OKADA 45 



both were present in nearly equal numbers. The onychasters are 

 only occasionally present in parenchymal regions. In the oxyhex- 

 asters, the diameter is usually 50^ to 75/x. The principals are of 

 moderate length and relatively slender, being about 8/x to lOju, long, 

 as measured from the central point of the axial cross. The slightly 

 swollen end of the principals bears 3 to 5 terminals in a diverging 

 tuft, smooth, tapering, generally nearly straight, but frequently 

 curved outwardly near the end. These spicules mostly occur on the 

 subdermal regions and closely resemble in general appearance those 

 occurring in E. inarshoili. 



EURETE SACCULIFORMIS. new species 



Plate 3, Figures G, 7 



Five complete colonies (cotypes, U.S.N.M. No. 22039) and two 

 other fragments of E. sacouliforniis are in the collection. They were 

 obtained 10 to 20 miles southwest of the Goto Island (Station 

 4890), at a depth of 135 fathoms, together with Aphrocallistes 

 heatrix orientalis Ijima. 



One entire specimen forms a hemispheroidal mass, which has a 

 diameter of 30 mm to 40 mm and a height of 24 mm to 35 mm. It 

 is attached at the base. The surface is plainly flattened by short 

 inferiorly expanded peduncles. The lobes are usually about 5 mm 

 thick, and the sponge appears as if it had been produced by a con- 

 tinued branching and anastomosing growth that started from centers 

 of the lower regions. The oscula are about 3 mm in diameter and are 

 bounded by a thick wall, not thinned out at the margin as is usual 

 in members of the present genus. (It is difficult to ascertain the true 

 features in greatly broken specimens.) 



The surface of the sponge appears slightly porous, owing to the 

 numerous afferent canals. In spots, especially in the oscular margin 

 of the tubes, the afferent canals are nearly closed, and the surface 

 has a heterogeneous appearance. 



Sficulation. — The dictyonal net forms an irregular and nearly uni- 

 form honeycomb. The hexactinic dictyonalia, which are joined in 

 a regular manner, form a net or latticework with irregular triangular 

 or quadrangular meshes. Fairly long, tuberculous, cylindrical 

 processes protrude from the dermal and gastral surfaces. Those 

 protruding from the dermal surface are distally expanded in a knob- 

 like swelling and are quite densely tuberculous, while those protrud- 

 ing from the gastral surface are conically pointed and sparsely 

 roughened. The beams composing the dictyonal net are sparsely 

 covered with small pointed tubercles. They are lOO^u to 120/x broad 

 at the middle, becoming broader at their intersections. 



