EEPORT ON THE MONAXONIDA. 149 



of the main skeleton, the largest being generally found at the ends of the primary fibres. 

 (3) Short, thick, straight, very bluntly pointed styli (PL XXIX. fig. 6), strongly spined 

 all over, size about 0'08 by 0"005 mm. ; echinating the skeleton fibre in great numbers. 

 (b) Microsclera ; of one kind only, viz., minute palmate isochelse about 0'005 mm. long. 



We have called this species after Dr. von Lendenfeld, who has a much fuller 

 acquaintance with the sponge (viz., in its native haunts) than we have, although he has 

 as yet published no description of it. 



The strong development of the horny fibre, with the coincident reduction in the 

 spicular element of the skeleton, and the form and great abundance of the echinating 

 spicules, are good characters by which to recognize the species. 



Locality. — Ofi" Port Jackson. One specimen. 



Clathria frondifera, Bowerbank, sp. 



1875. Halichondria frondifera, Bowerbank, Proc. Zool. Soc. LonJ., April 1875, p. 288. 

 1880. AmiMlechis frondifer, Vosmaer, Notes from the Leyden Museum, vol. ii. p. 115. 

 1884. Clathria frondifera, Eidley, Zool. Coll. H.AI.S. "Alert," Brit. Mus., pp. 448, 612, pi. xlii. 



fig. j : pi. liii. fig. J. 



This is a widely distributed and very common shallow-water species, and has been 

 already described by two authors (Bowerbank and Eidley, loc. cit), hence it is not 

 necessary to enter into further details regarding it in this place. 



XocaZ%.— Station 188, September 10, 1874; lat. 9° 59' S., long. 139° 42' E.; west 

 of Torres Strait ; depth, 28 fathoms ; bottom, green mud. One fine specimen. 



Habitat. — Strait of Malacca ; Gaspar Strait (Bowerbank) ; west of Torres Strait 

 (Challenger) ; Thursday Island ; Prince of Wales Channel, Torres Strait ; Percy Island 

 and Fitzroy Island, Queensland ; Providence Reef and Island, Mascarene Group ; 

 Amirante Islands; SeycheUe Islands (Ridley, "Alert"). 



Clathria elegantula, Ridley and Dendy (PI. XXVIII. figs. 3, 3a; PI. XXIX. figs. 14, 

 14a, lib). 



1886. Clathria elegantula, Eidley and Dendy, Ann. and Mag. Nat. Hist., ser. 5, vol. xviiL p. 474. 



Sponge (PI. XXVIII. fig. 3) sessile, the single specimen present consisting of 

 several much flattened, expanded, divided lobes, based upon half of a dead bivalve 

 shell. Height 81 mm., greatest breadth about the same. Thickness of lobes usually 

 about 10 mm. The margins of the lobes are more or less deeply notched and 

 slightly undulating. Colour in spirit pale, brownish-yellow. Texture soft and 

 spongy, elastic and fibrous ; internally rather cavernous. Surface very uneven, 

 beset with numerous projecting conuli, between which is stretched the thin, semi- 



