1881.] THK SURVEY OF H.M.S. *ALERT.' 135 



Examined, In spirit, and by sections in balsam and in spirit. 



Ilab. Victoria Bank (off S.E. Brazil), 39 fathoms ; bottom, 

 coral. Six specimens, one young. 



Obs. This Sponge shows a considerable amount of variation in 

 the size of the spicules in different specimens. One variety is espe- 

 cially well marked : its length is only twice as great as the breadth ; 

 its acerates reach the diameter of "09 millim. and length of S-O' 

 millims., its triradiates increasing proportionally in size, the diameter 

 reaching •0.5 millim. It appears to be most closely allied to A. 

 {Leucandra) asperum, Hiickel, from the Mediterranean, of described 

 species ; but differs from it in the inferior ratio of the thickness of the 

 acerates to that of the triradiates, in the much thinner body-Avall, 

 in the larger and more slender apical ray of the quadriradiate, and 

 in the formation of the oral fringe out of a special fine acerate form of 

 spicule. 



Aphroceras caminus, Hiickel (Plate XI. fig. (!), and var. 

 CRAssioR, sp. nov. (Plate XI. fig. 7). 



Leucandra camitius, Hiickel, Kalkschwiimme, ii. j). \7^, pi. .xx.\i. 

 figs. la-Id, .\x\vii. figs. 5 A, 5 B, 6. 



Three specimens occur in this collection from the same locality, 

 two of which are apparently identical, and one differs cousider.ably 

 from them. The arrangement of the canal-system has not been made 

 out very clearly; but it appears to be of the " traubenfcirmig " 

 type described by Hackel (o^j. ciL vol. i. ]). 233) in A. (L.) ananas, 

 Montagu, &c. with small circular cavities scattered through the 

 walls of the body. 



The two specimens, wJiich agree with each other and mt\\ Hackel's 

 description, are ovate, G to 7 millims. long by about 4 millims. 

 broad; the body-wall is T.'i millim. thick at the sides; the month 

 is funnel-shaped owing to the downward convergence of the walls of 

 a slightly projecting "collar," which is 2*5 millims. across; the 

 body-cavity is about 1 millim. broad. The other specimen, which 

 may be termed var. crassior, is 7 millims. long by 1 broad; body- 

 wall To millim. thick at sides ; mouth probably about the same 

 as in the normal forms (most of it has been broken awav). The 

 microscopic characters are tabulated below. Var. crassioi; how- 

 ever, has the triradiates much larger (maximum size of ray of those 

 of caminus='6^t by 'O/o millim.), the angles are all equal, not 

 paired. The acerate is apparently longer; and the rays of the qua- 

 driradiates are straight, instead of the laterals and the apical being 

 bent (as in caminus). Perhaps therefore crassior constitutes another 

 species ; but in the face of the single imjterfect specimen it" will be 

 well to await better information. 



