90 THE VOYAGE OF H.M.S. CHALLENGER. 



Mid-Pacific; depth, 2750 fathoms; bottom, Radiolarian ooze; bottom temperature, 35 "'l. 

 One specimen. 



Cladorhiza abyssicola, Sars, var. linearis, nov. (PI. XX. fig. 6 ; PI. XXI. figs. 2, 2a). 



Under this name we include three denuded skeletons of a Cladorhiza (PI. XX. 

 fig. 6) obtained in the South Pacific at a depth of 2385 fathoms. Each consists of a 

 long, straight, slender spicular axis about 106 mm. in length, with a few remaining 

 short tufts of spicules projecting fi-om it in places ; entangled in some of these tufts 

 are a few microsclera, the size and shape of which induce us for the present to consider 

 the three specimens as a variety of Cladorhiza abyssicola, Sai\s, though very probably 

 the examination of more perfect specimens may ultimately show them to be specifically 

 distinct, or more nearly allied to Esperella biserialis, nobis, from the same station. 



The anisochelate spicules are of fair size and have a strongly curved shaft, expanded 

 towards the large end, and with only three short teeth at each extremity ; they measure 

 about 0"032 mm. in length. 



The sigmata are large, apparently not contort, measuring about 0'17 by O'Ol mm. 



The megasclera (PI. XXI. figs. 2, 2a) are long, slender styli of very beautiful shape, 

 much resembling those of Esi^erella biserialis, but the short tylostyli of the latter are 

 not present. In the stem the styli may attain a length of nearly 3 mm. 



Locality. — Station 281, October 6, 1875 ; lat. 22° 21' S., long. 150° 17' W.; South 

 Pacific; depth, 2385 fathoms; bottom, red clay; bottom temperature, 34°'9. 



Cladorhiza moruliformis, Eidley and Dendy (PI. XX. fig. 3 ; PI. XXI. figs. 1, 15, 19). 



1886. Cladorrhiza moruliformis, Ridley andDeady, Ann. and Mag. Nat. Hist., ser. 5, vol. xviii. 



p. 342. 



Sponge (PL XX. fig. 3) consisting of a small, globular head, perched on the summit 

 of a stalk. A large number of short, stout, conical processes, all of about the same size, 

 arise from the head in every direction, giving to it the appearance of a mulberry (whence 

 the specific name). The main stalk, or axis of the sponge, is prolonged through the 

 head, and projects for a short distance vertically above it {vide woodcut. Fig. 3). 

 Diameter of the head, exclusive of the conical processes, 10 mm. Length of 

 conical processes 2 mm.; transverse diameter of same 1 mm. Length of stalk still 

 attached to the head (it has evidently been broken off short) 2 mm. ; diameter of 

 same 2 mm. Length of part of axis projecting above the head 2*5 mm. Colour, 

 when dried, white. Texture fragile. 



Skeleton. — (l) A main axis of spiculo-fibre is continued from the stalk, of which it 

 forms the chief part (if not the whole), right through the globular head, projecting 

 for a short way beyond the top of the sponge. (2) From this stalk, starting from near 



