REPORT ON THE KERATOSA. 69 



Carteriospongia otahitica, Esper, sp. (PI. IV. fig. 4). 



Spongia otahitica, Esper, Pflanzenthiere, Bd. ii. p. 270. 

 Carteriosjjonffia otahitica, Hyatt, Revision, &c., voL ii. p. 541. 



This species, represented in tlie collection by numerous specimens from Admiralty 

 Islands, was established in the year 1794, and there are in spongiological literature 

 many descriptions of it. Accordingly, I consider it unnecessary to enter here into parti- 

 culars, and refer the reader to the best of these descriptions, that of Hyatt, in the hope 

 that with the help of my drawing on PI. IV. the characters of the species may be easily 

 comprehended. 



Colour. — Dirty pale yellowish. 



Habitat. — Off Wild Island, Admiralty Islands; reefs; March 1875. 



Family APLYSiNiDiE, Vosmacr. 



Aplysince (e.p.), Hyatt. 

 Ceratina (e.p.). Carter. 

 Aplysinidce (e.p.), F. E. Schulze, v. Lendenfeld. 



Keratosa with small either hemispherical or pear-shaped flagellated chambers com- 

 municating with exhalent and inhalent cavities, each by means of one comparatively long 

 and narrow inhalent and exhalent canaliculus. Axis of fibres thick ; ground-mass in 

 the neighbourhood of the flagellated chambers overloaded with granules. 



L^iffaria, 0. Schmidt. 



Aplysinidse with thick-walled heterogeneous skeletal fibres, their central part but 

 little difi"erentiated optically from the surrounding horny lamina. 



Luffaria variabilis, n. sp. (PI. IX. figs. 1-6). 



As I remarked before (p. 33), I am not prepared to say whether all Liiffarice in 

 addition to thick skeletal fibres also possess fine ones. But should such be the case, 

 the species I am going to describe may still be readily distinguished from all others of 

 the genus by the following peculiarities ; its skeletal fibres are not at all so glass-like 

 and fissile as Schmidt states with regard to the specimens he had for examination. 

 Again, though on the whole its skeleton admits of comparison with a burst but still 

 only with a very imperfect one, the distance between the prominent outer fibres reaching 

 1 to 2 mm. In addition to some small fragments, the species is represented in the 

 Challenger collection by two sj)ecimens, one of massive shape, the other on the contrary 



