378 COLLECTIONS FROM MELANESIA. 



Terms employed, — These are essentially those used by Mr. Carter, 

 as in my Peport on the ' Alert ' collections from the South-American 

 coast (Proc. Zool. Soc. 1881). The measurements given for spi- 

 cules are the averag, maximum measurements; the diameter of a 

 spicule is its greatest diameter; spines are not included in spicule- 

 measurements. 



CERATOSA. 



Ceraospongiae, Schmidt, Spong. Adr. Meer. and Atl. Geb. 



SPOXGIID^E. 



Bibulida, and Hircinida, pars, Carter, Ann. §■ Mag. N. li. (4) xvi. 

 p. 1.32. 



1. Cacospongia mollior. 

 Schmidt, Adr. Meer. p. 27. 



A specimen in spirit, pedicellate, consisting of one prominent lobe 

 and a lower broader portion, and a fragmentary skeleton. The apices 

 of the conuli are about 2 millim. apart ; the consistence is firm but 

 compressible and elastic, the dermis black and glabrous, the sarcode 

 rather opaque yellowish brown ; the primary fibres long, straight, 

 and with very rare foreign bodies, diameter 1 millim. ; the secon- 

 daries making very various angles with the primaries, and forming 

 numerous irregidar meshes of variable size and angular shape ; 

 diameter of fibre - U35 to -U7 millim. ; fibre of both kinds coarselv 

 laminated. 



The specimen is 68 millim. (2 J inches) high, 25 millim. in greatest 

 breadth, 12 millim. in greatest thickness, and seems to agree in the 

 main with Schmidt's species, although the network of the fibre is 

 less regular and close. 



Hah. Prince of Wales Channel, Torres Straits, 5-7 fms. 



Distribution. Adriatic (Schmidt). 



2. Euspongia foliacea. 



? Spongia foliacea, Esper, Pflanzenthiere, Fo) /-<<tz. i. p. 201, pi. lvi. 

 ? Platychalina foliacea, Ehlers, Die Esj/ersc/i. Spong. p. 21. 



It is with much regret that I have to express a doubt whether 

 the sponge for which that careful observer, Prof. Ehlers, established 

 the above genus is, as he asserts, a Chalinid. My reasons are as 

 follows : — From H.M.S. ' Alert ' there has been obtained a sponge, 

 in fine preservation although dry, agreeing minutely with Esper'a 

 figure and description, except that the " pores " are smaller and more 

 scattered and numerous, and not placed on the back, but on the 

 front. With the exception of a very few fragments of spicules of 

 different thicknesses, found singly and rarely in a ivw fibres, there 

 are no spicules at all, and the sponge is evident ly a Ceratose species, 

 differing from the common species of Euspongia only in its flattened 

 form. The fibres of the main skeleton agree in their consistency 



