404 COLLECTIONS PEOM MELANESIA. 



The maximum lateral extent of the largest of the specimens 

 appears to have heen about 270 millim. (10| inches), another 

 measures 250 millim. (10 inches) across the branches, while indi- 

 vidual branches may attain a length of 90 millim. (3g inches). In 

 habitus the species differs from T. folioides mainly in having the 

 general surface approximately even, and not asperated by projecting 

 points ; in the structure of the fibre, the homy element shows a far 

 greater development, and the triourvate is much stouter than in that 

 species. 



34. Toxochalina murata*. 



Low, broad, wall-like masses, enclosing a series of vertical tubes, 

 5 to 8 millim. in diameter, which rise straight from near the base of 

 the mass, and are separated by 8 to 10 millim. of sponge-substance ; 

 the mouths of the tubes may project slightly, but are rather con- 

 tracted. General surface of sponge asperated with low, sharp, 

 monticular elevations 3 to 7 mUlim. apart, 1 to 2 millim. high, often 

 connected by low ridges ; surface between ridges and elevations 

 smooth in dry state. Texture in dry state elastic but firm ; colour 

 pale yellowish brown. Fibre very tough. 



Main skeleton — meshes chiefly very wide, rectangular, formed by 

 primary and secondary fibres of approximately equal diameter ; at 

 intervals a less regular network of smaller secondary fibres combined 

 with the straight primaries ; larger fibres -022 millim. broad, smaller 

 ■0095 to '016 millim. ; primaries cored by 1 to 4 series of axiaUy 

 placed acerate spicules, sometimes wanting ; secondaries by 1 to 2 

 series, often wanting altogether. Colour of fibre pale yeUow-brown. 



Spicules — (1) skeleton acerate, straight, smooth, tapering to very 

 sharp points from about two diameters from ends, size -1 by '005 

 millim. ; (2) tricurvate acerate of sarcode, smooth, curves gentle, 

 tapering gradually to fine points, size '063 by -0016 millim. 



Sah. Port Molle, Queensland, 12-20 fms. 



The average greatest height of the single (dry) specimen i830 miUim. 

 (1| inch), the total length (from side to side) 140 millim. (5| inches). 



This species has very much the external habit of T. folioides, var. 

 vallata, but the points on the • surface are less prominent than in 

 that species ; the very strongly horny character of the fibre sepa- 

 rates it more decidedly, so that it is impossible to confound the two 

 species under the microscope. In the case of T. robusta, mihi, the 

 repent habit, the solid and smooth branches, and the slighter and more 

 strongly spiculate fibre constitute ample means of differentiation. 



35. Fachychalina lobata, var. 



F Spongia lobata, JEsper, Pfianzenth. ii. p. 273, pi. xlvi. 



I have thought it best to assign, with doubt, to the above species 

 (as a variety) a form with strong, rudely cylindrical main axis- and 

 branches, which was apparently semideoumbent in life, and which 



* From Lat. muratus, walled. 



