EUSPONGIA. 131 



variety, and measure 0- 12-0-2 millim. in thickness ; they are completely filled 

 with foreign bodies, chiefly sand-grains. The surface of the main fibre is 

 slightly knotty. The connecting-fibres form a very regular network with 

 rounded polygonal meshes, which are 0-1-0-3 millim., on an average 0-16 

 millim., wide. The fibres are straight and very abruptly angularly bent at the 

 joining points ; they are 0-025-0-033 millim. thick. I do not consider it 

 necessary to divide this variety further, as Hyatt has done. 



I am rather doubtful whether aU the sponges which Hyatt places in his 

 species lignea really belong to this variety, but it is not possible for me to 

 decide this. 



Geographical Distbibutioit.— Bermudas (Peahochj Academy Coll). Mau- 

 ritius {Museum Comparative Zoology Coll.). Peari Island, Panama Bay {Tale 

 College Coll.). 



West coast of Australia : Western Australia (Baily). South coast of Aus- 

 tralia: Vort 'Phimp,Y. (Le)idenfeld). East coast of Australia: Port Jackson, 

 N. S. W. {PUladelpUa Acad. Coll.). 



Euspongia bailyi, Lendenfeld. 



Eiispongia bailyi, E. v. Lendenfeld, " A Monograph of the Australian Sponges. 

 —Part VI. The Genus Euspongia" Proceedmgs of the Linnean Society 

 of New South Wales, vol. x. p. 535 (1885). 



Large, erect, cup-shaped sponges, which are attached by a broad base. 

 The sponge generally consists of a single, pretty symmetrical cup; some- 

 times, however, two cups may be fused to form a single sponge. The whole 

 sponge attains a height of 200 millim. and a similar width. The cup is 

 comparatively shallow, its depth being, in tall individuals, equal only to a third 

 of the height. In those, however, which are low and broad the cup may be 

 two thirds as deep as the whole sponge is high. In every case there is a very 

 large, solid, basal mass, the upper part of which only grows out on its margin 

 to form the cup. The cavity of the cup is semispherical. The margin is 

 regularly circular. 



The outer surface of the skeleton is very rough and uneven, covered 

 with high, irregularly longitudinal ridges, from which high villi and other 

 irregular outgrowths of varying shape arise. The inner side of the cup is 

 comparatively smooth ; here numerous round holes, averaging 3 millim. in 

 diameter, the oscula, are situated. These are very abundant at the base of the 

 cup, but absent near the margin. The dry skeleton is light brown, pretty 

 soft, and elastic. 



The main fibres are straight, on an average 0-7 millim. apart, and extend 

 from the base upward and outward, terminating in the villi on the outer sur- 



k2 



