274 Mr. R. Kirkpatrick on the Moncuvonellida 



same spicular elements, but of different dimensions, and liaf5 

 the labis amono- its microscleres. 

 Localily. Off Balleney I., 254 £atb. 



Hymerrhaphia rufa, sp. n. 



The sponge forms a thin raud-coloiired brown crust on a 

 branched Polyzoon. The surface is smooth, and no pores or 

 oscules are visible. The consistence is rather tougli. 



The skeleton of the choanosonie is formed of longer and 

 shorter acanthostyles dressed vertically, that of the ectosome 

 being formed of tangential ly arranged anisotornotes, either 

 isolated or in bundles. 



S]>icules. — Megascleres : larger acanthostyles, 312 x 25 M^, 

 swollen at the head, spined all over, with larger curved spines 

 at the head. Smaller acanthostyles, 131 x 18*75 a*. Aniso- 

 tornotes of ectosome, 344x12 fi, straight, fusiform, attenu- 

 ating gradually at one end but abruptly at the other. 



Microscleres : isancorge, 28'5 /u, long, with three or four 

 teeth at eacb end ; rarely the teetli are not developed, the 

 ends being in the form of hemispherical cups. 



Dredged near Winter Quarters, No. 10 hole, 130 fath. 



Ophlitaspongia nidijicata, sp. n. 



Sponge massive, of an inverted pyramidal shape, sessile, 

 narrow and contracted at the point of attachment. Surface 

 uniformly coarsely spinous. Circular oscules ("7 mm. in 

 diameter) on the upper surface, at the bases of the spines ; 

 (pores closed). Subdermal cavities fiat and shallow. Flagel- 

 lated chambers diplodal. Colour dirty grey, the tips of the 

 spines being yellowish. CJonsistence hard and tougli. 



Skeleton consisting of dense branching axes of styles 

 cemented with spongin and ecliinated by smooth styles 

 passing at right angles from the axis to the surface. Ecto- 

 somal sjjicules in form of slender straight styles. Consider- 

 able tracts of dermal membrane were devoid of these spicules. 



iSjncules. — Megascleres : large, straight, smooth styles, on 

 an average about 1000 x 50 /jl. Also smooth curved kind, 

 625 p, long. Ectosomal styles straight, smooth, tapering 

 gradually to a point, 406 x /x. 



Microscleres : toxa smooth, 638 /x long, 6"25 p, thick at the 

 centre. These spicules occur in nests or groups of five ta 

 ten. 



This new species comes well within the genus Ophlita- 

 spongia, 15k., as emended by Ueiidy. O. scriata, Bk., 0. sub- 

 liiapidii^ (Jartcr, and O. inembranacea, Tliiele, all have toxa. 



