540 HIPPOSPONGIA, 



the primaries, the differentiation between primaries and secondaries becomes 

 indistinct. This becomes particularly apparent between main fibres, which lie 

 close together. 



Geographical Distribution. — South coast of Australia : Port Phillip, V. 

 i^Lendenfeld), 



Hippospongia canaliculata, var. moUissima, Lendenfeld. 



Euspoiigia canaliculata, var. mollissima, E. v. Lendenfeld, " A Monograph of 

 the Australian Sponges. — Part VI. The Genus Eusjjoncjia," Proceedings 

 of the Linnean Society of New South Wales, vol. x. p. 502 (1885). 



The main fibres ai'e on an average 0-9 millim. apart and 0-14 millim. thick. 

 They contain foreign bodies, small sand-grains measuring only 0-014 millim., 

 in great abundance. Their surface is roughened by a few small knobs. 

 These fibres are never straight or gracefully curved, but appear irregu- 

 larly bent and twisted, a peculiarity which characterizes the variety. The 

 differentiation betwesn primary and secondary connecting-fibres is still less 

 clearly expressed than in the foregoing variety, although also in this one the 

 two can be distinguished, at least in certain parts of the sponge. The pri- 

 maries are composed of straight portions, which join at angles not so near to 

 180° as in the previous variety. Occasionally the portions between the joining 

 points are slightly curved. The primaries are 0-4 millim. apart, and on an 

 average 0-032 millim. thick ; their thickness is, however, subject to unusual 

 variations and not proportional to the length of the fibres, as in the other 

 varieties. The secondaries form a very ii*regular network, and there are no 

 simple unbranched ones at all. The meshes average a diameter of 0*2 millim. 

 The secondaries vary A^ery much in thickness, from 0-008 to 0-03 millim. ; some 

 of them are as thick as the primaries, 



Geogeapiiioal Distribution. — East coast of Australia : Port Jackson, 



N. ^.W.{Le7idenfeld). 



Hippospongia reticulata, Lendenfeld. 



Euspongia reticidata, E. v. Lendenfeld, "A Monograph of the Australian 

 Sponges. — Part VI. The Genus Euspongia" Proceedings of the Linnean 

 Society of New South Wales, vol. x. p. 541 (1885). 



A mass of reticulating folded lamellsB attaining a length of 350 millim. 

 and a height of 200 millim. The vestibular spaces have an average 

 w'idth of 20 millim., the apertui'es on the surface which lead into them are 

 10-15 millim. wide, circular or irregular. The external surface is conulated, 



