SPONGES.-HALLMANN. l6i 



[1888. Not Clathriii aiisti-dlis, Lendenfeld, Cat. Sponges 



Austi'. Mus., 1888, p. 22J.] 



Sessile to sitbstipitate : sonietivies ratlwr massive, but 

 usually growing in the form of a thick erect plate which 

 may either remain simple or become variously modified 

 by proliferation, e.g., by partial or complete bifurcation 

 into parallel plates, by the development of variously dis- 

 posed lamellar outgrowths, or by the formation of lobes. 

 Oscida small, mostly marginally situated. Both surfaces 

 of the plate or plates traversed, immediately beneath the 

 dermal membrane, by sub-parallel longitudinal canals 

 which terminate in the oscula. Fibres very densely 

 echinated ; the coring spicules chiefly acantho styles. 

 Foreign bodies, chiejly sand grains, occur in variable 

 amount in the fibres, and occasionally also in the ground 

 substance. Interstitial megascleres, consisting chiefly of 

 accessory acanthostyles, are extremely abundant. Dermal 

 skeleton reticidate, without admixture of oxea. Mega- 

 scleres, maximum sizes: — (i.) Oxea, 200 x 6 ;<; principal 

 acanthostyles, 160 x 11 pi; dermal acanthostyles, loo-iio 

 X 8-g fi. Isochelce arcuatce, not distingtiishable into two 

 groups, 12 to iS fi long. 



Introductory Remarks. — The sponges described by White- 

 legge under the name of Plumohalichondria australis, 

 Lendenfeld, are separable into two varieties — the one, 

 corresponding to those which he identified with Clathria 

 australis, Lendenfeld ; the other, to those which he re- 

 garded as representing three of Lendenfeld's species, viz., 

 Echinonema levis, E. rubra and Clathria macropora. In 

 the case of none of the four species mentioned, does 

 Lendenfeld's description agree with that of Whitelegge, since 

 for each of them the coring spicules were stated to be styli, 

 whereas in Plumohalichondria australis, Whitelegge, they are 

 oxea. What were the sponges which Lendenfeld had before 

 him, will probably never be known with certainty, but after 

 taking all the evidence into account, I am inclined to believe 

 that Whitelegge's identifications of E. levis and E. rtdrra are 

 correct, those of C. australis and C. macropora wrong. The 

 two former as well as Whitelegge's C. macropora I will des- 

 cribe as Crella incrustans, var. levis : Lendenfeld's C. australis 

 and C. macropora are unknown to me. Whitelegge's C. 

 australis, the subject of the following description, I regard as 

 identical with Carter's Plumohalichondria arenacea. Clathria 

 australis, Lendenfeld, would appear to resemble this last- 

 mentioned only in external form ; for according to its des- 

 cription, the skeleton is reticulate, the main fibres are entirely 



