12 LEVCANDRA. 



Leuconia typica, var. tuba, Polejaeff, Report ou the Calcarea, The Zoology 

 of the Voyage of H.M.S. ' Challenger,' part xxiv. p. 56 (1883). 



This sponge attains a length of 40 millim., and an average diameter of 

 12 millim., the thickness of the body-wall is 3 millim. The spherical ciliated 

 chambers have in this species particularly regular outlines, and are smaller 

 than in any other allied forms, their diameter rarely exceeding 0*03 millim. 



Skeleton. — Gastral tetrad Spicules. Basal ray straight, tapering from the base 

 to a sharp point, usually shorter, 0-18 millim., and rather thinner than lateral 

 rays, forming with each of these latter an angle varying from 105° to 110° ; 

 lateral rays more or less cylindrical, either straight or slightly curved forwards, 

 rarely exceeding 0-225 millim. in lengch, and 0*015 millim. in thickness ; 

 apical ray curved, more or less sharply pointed, length not exceeding 

 0*06 millim., variable. This ray is often rudimentary; and there are 

 amongst the tetract spicules many triact spicules also. — Triact spicules of the 

 Parenchyma mostly quite regular ; rays straight, smooth, tapering from 

 the base to sharp points, reaching 0*75 millim. in length, and 0-065 millim, 

 in diameter. — Dermal triatc Spicules. Sagittal, all rays of the same length, 

 rarely exceeding 0-35 millim., and of the same diameter, 0-02 millim., either 

 tapering from the base to sharp points, or of a cylindrical form ; basal ray 

 straight ; lateral rays curved forwards, forming each with basal ray an angle of 

 about 115°. — Diact Spicules. In the walls of the body, sparsely scattered here 

 and there in the parenchyma, either isolated or in groups, fine linear, straight, 

 occasionally slightly curved, 0-3 millim. long ; near the osculum piercing the 

 wall in perpendicular direction, either spindle-shaped or rather cylindrical, 

 but sharp-pointed, straight, or slightly curved, 0-1 millim. long, 0-004 millim. 

 in diameter. 



Geogeaphical Disteibution. — North Atlantic : off Bermudas, 32 fathoms, 

 mud (' Challerujer '). 



East coast of Australia : Port Jackson (Lendenfeld). 



Leucandra villosa, Lendenfeld. 



Leucandra villosa, E. von Lendenfeld, " A Monograph of the Australian 

 Sponges.- — Part III.," Proceedings of the Linnean Society of New South 

 "Wales, vol. ix. part 4, p. 1131 (1885). 



This sponge appears in the shape of a very large, thin-walled, and irregular 

 sac, with an extremely wide osculum. These sacs, of an irregular cylindrical 

 or oval shape, attain a length of 50, and width of 25 milhm. and more. They 

 generally appear compressed, with an oval transverse section, the lai-ge axis of 

 the eUipse about twice as long as the small one. The osculum is nearly as 



