42 THE T^OYAGE OF H.M.S. CHALLENGEE. 



the soft parts ; the osciila, scanty in the incrusting specimen, proved to be thoroughly 

 deficient in that of leaf-like shape ; one of the specimens proved to be sterile ; the other 

 was provided with numerous sperm-balls. The habitat of Spongelia sjnnifera, hitherto 

 found only in the Adriatic, is now extended to the east coast of Australia. 



Colour. — Pale greyish and dirty yellowish. 



Habitat. — Off Port Jackson, depth 7 fathoms. 



Spongelia pallescens, 0. Schmidt (PI. III. fig. 1). 



This species, whose detailed definition we owe also to F. E. Schulze,^ has been divided 

 by him into two subspecies, and each subspecies in its turn split into two varieties. The 

 numerous Challenger specimens of Spongelia pallescens are all to be determined as sub- 

 speciesfragilis var. ramosa, but I must add that while the diagnosis of this variety as 

 given by F. E. Schulze is thoroughly applicable to the Challenger specimens, the meshes 

 of their skeletons proved to be of rather larger diameter than those of any of the 

 Spongelidse with anastomosing fibres examined by F. E. Schulze, and whose skeletons, 

 through his kindness, have all been placed at my disposal. Whether this diSerence is of 

 individual or varietal or even specific value, I am unable to decide, and therefore limit 

 myself to merely mentioning it. 



Colour. — Pale yellow and lilac. 



Habitat. — Bahia, shallow- water. 



Spongelia horrida, Selenka (PI. III. fig. 2). 



Spongelia horrida, Seleuka, Zeitschr. f. wiss. ZooL, Bd. xvii, p. 566, pL xxxv. figs. 1-4, 1867. 



This species, placed by Selenka in the genus Spongelia, has also been adopted by 

 F. E. Schulze,^ but apparently only on account of its form and the properties of the 

 skeleton. I am pleased to be able to sanction this proceeding, as the external shape and 

 structure of the skeleton of the Challenger specimens agree closely with those of the 

 forms described by Selenka, and their internal organisation is that of a typical Spongelia. 

 The identification of the forms in question is, on the other hand, confirmed by the fact 

 that both the Challenger and Selenka's specimens were from Australia, 



The Challenger Collection possesses three specimens of Spongelia horrida; two are 

 in the form of crusts 12 to 18 mm. high, the third being of a more massive appear- 

 ance. But all three specimens are equally constant to the main character of the 

 species, the meshes of their skeleton being far larger than in any other Spongelia, as may 

 be seen on PI. III. fig. 2. The foreign enclosures of the fibres proved to be chiefly 



I Zeitschr. f. wiss. ZooL, Bd. xxxii. p. 154, 1879. ^ Ihid., Bd. xxxii. p. 122. 



