AKT. 12 HEXACTINELLID SPONGES OKADA 25 



tubercles sparsely and irregularly scattered over the surface. The 

 rather flat terminal disks are 70/x to 125/x high, 104/la to 120,a broad, 

 on an average, and have eight broad, spadelike marginal teeth. 

 These amphidisks are scattered sparsely in the derm over the su- 

 perior regions of specimen A, while on the inferior regions and 

 on all parts of specimen B they are found abundantly. 



Ellipsoidal mesamphidisks (fig. 2, h) of varying size, GO|Li to 80)m 

 long on an average, are abundant. The shaft is slender, 4ju. broad, 

 and covered with numerous sharp spines. The high, bell-shaped 

 terminal disks, 2-iju. in breadth, usually have 10 to 12 narrow mar- 

 ginal teeth. On the basal regions of both specimens A and B there 

 exist much larger mesamphidisks, which measure 10();u, to 145/x in 

 length. These have also 10 to 12 marginal teeth, 48/i in length at 

 the bell-shaped terminal disk, which measures 40/;i broad. 



The micramphidisks (fig. 2, j) are most numerous and lie scattered 

 irregularly in the dermal and gastral membrane. In fewer numbers 

 they are found in the parenchyme. They are IQjx to 20jm long and 

 have hemispherical terminal disks with numerous marginal teeth. 



iSIicroxyhexactins (fig. 2, k) are abundant in the parenchjnne. 

 Their rays are QOfi to SO/j. long, 4;u thick at the base, straight, and 

 covered throughout witli small tubercles, making the surface 

 appear rough. The curved, rayed microxyhexactins are totally 

 absent. Occasionally similar-sized pentactins (fig. 2, '??i) and stau- 

 ractins (fig. 2, /) are found. In the pentactins the distal unpaired 

 ray is much shorter than the paratangential rays, measuring 40/x 

 long. 



The present new species somewhat resembles H. indlcuni anda- 

 mancnse F. E. Schulze, but differs from it by having differently 

 shaped gastral pinnies and the poplar-tree-shaped diactinic mar- 

 ginalia. 



HYALONEIMA (COSCINONEMA) KIRKPATRICKI GLOBOSUM, new subspecies 



Plate 2, FiGur.B 3 



Stations 4956 and 4957, where the two specimens of this sub- 

 species were captured, are not far apart. The best preserved speci- 

 men (designated holotype, U.S.N.INI. No. 22031) has a nearly trun- 

 cated cone and is 135 mm long. Its root tuft, however, has been 

 entirely torn off. The broader upper end has a diameter of 85 nun. 

 The lateral dermal surface of the sponge body is more or less 

 crushed and injured, but in most of it the quadrate dermal lattice- 

 work is well preserved. The sieve plate is deeply depressed in the 

 center and raised toward the margin to form a low ring wall with 

 a somewhat sharp edge. The surface is perforated by more or less 

 circular, irregularly scattered apertures, 1 mm to 4 mm wide. The 



