REPORT ON THE MONAXONIDA. 59 



Desmacella annexa, Schmidt. 



1870. Desmacella vagahunda, var. annexa, Schmidt, Spong. Atlant. Gebiet., p. 53. 

 1874. Desmacella pumilio, Carter, Ann. and Mag. Nat. Hist., ser. 4, vol. xiv. p. 250. 

 1880. Desmacodes vaffahundics, var. annexa, Vosmaer, Notes from the Ley den Museum, vol. ii. 



p. 108. 



AVitli this species we identify a small fragment from Station 24. The most 

 characteristic feature of the species is the presence of numerous very fine toxa, measuring 

 0"09 by O'OOl mm. These toxa also occur in Schmidt's type specimen, as attested by a 

 preparation in the British Museum, although Schmidt and Vosmaer both refer to them 

 simply as " acerates." 



The identification of Mr. Carter's species was made after a comparison of his account 

 with the sUdes representing Schmidt's species in the British Museum. 



ioca%.— Station 24, March 25, 1873 ; lat. 18° 38' 30" N., long. 65° 5' 30" W.; 

 West Indies ; depth, 390 fathoms ; bottom, Pteropod ooze. 



Habitat. — Florida (Schmidt); English Channel (Carter); West Indies (Challenger). 



Subfamily 5. Hamacanthin^. 



1872. Hamacanthidx, Gray, Ann. and Mag. Nat. Hist., ser. 4, vol. ix. p. 449. 



1886. Voviefi-idinx, Ridley and Dendy, Ann. and Mag. Nat. Hist., ser. 5, voL xviii. p. 337. 



Megasclera oxea or styli. Microsclera large diancistra, to which others may be 

 added. 



We 23ropose to recognise in this subfamily two genera, according as the megasclera 

 are oxeote (ranging to strongylote) or stylote. In the one genus, Hamacantha, Gray,^ the 

 only species yet known to us is Bowerbank's Hymedesmia johnsoni,^ a species which 

 appears to have been never yet described, although Dr. Bowerbank figures the 

 characteristic diancistra (loc. cit.). Examination of the preparations in the British 

 Museum has shown us that the megasclera are oxeote. The second genus is Vomerida, 

 Schmidt, in which the megasclera are stylote. 



Unfortunately the genus Hamacantha is not represented in the Challenger 

 collection. 



Genus Vomerula, Schmidt (Pis. XII., XVII.). 



1874. Haliclwndria, pars, Bowerbank, Mon. Brit. Spong., vol. iii. p. 208. 

 1880. Vomerula, Schmidt, Spong. Meerb. von Mex., p. 82. 



1885. Hamacantlia, pars,\osma.ei; Sponges of the " Willem Barents" Expedition, 1880-81, 

 p. 28 {sep) ; nee id., Bronn's Klass. u. Ordn. d. Thierreichs, Porifera, 

 p. 352, wee Gray, Proc. Zool. Soo. Lond., 1867, p. 538. 

 Megasclera styli. 

 This genus has been wrongly characterised by Vosmaer as distinguished by the 



1 Proc. Zool. Sac. Lond., 1867, p. 538. ^ jzirf^ Mon. Brit. Spong., vol. i. figs. 112, 293. 



