Sponges from South Australia. 279 



specimens of C. nucula from " Port Phillip Heads " &c. 

 4-6000ths ; in G. secunda, Lend., 18-6000tlis; in C. sacci- 

 formis, Cart. (Mauritius), 27-6000ths ; and in G. pajnllata, 

 Lend., 4-6000ths. 



I omitted to mention that in all the Chondrillce there appears 

 to be a horizontal, more or less interrupted cavity traversed by 

 filaments between the cortex and the body, like the subdermal 

 cavities of sponges generally, which not only marks the divi- 

 sion between the two, where they are easily separable, but into 

 which the pores empty themselves before their contents are 

 continued on to the interior of the body. 



Such a line of demarcation does not appear in the varieties 

 of Halisarca above mentioned. 



Order II. CERATINA. 



Having also in my descriptions of the Australian species in 

 this order, which have been already published, omitted to pre- 

 mise, for more convenient reference, the classificatory arrange- 

 ment of 1875, it is herewith supplied as tabulated at p. 188 

 {op. et loc. cit.). 



Fam. 1. Luffarida. 



2. Aplysinida. 



3. Pseudoceratida. 



For the characters of these " families" respectively I must 

 refer the reader to p. 134 &c. (/. c), where they are given in 

 eortenso', while I take this opportunity of briefly stating 

 whence the names of the first and second families here have 

 been derived. 



In 1794 Esper described and illustrated a species named 

 '•'• Spongia fistularis^'' ('Pflanzenthiere,' vol. ii. tab. 21 a), which, 

 in 1816, Lamarck identified with one of the same kind in his 

 "Cabinet" (Anim. sans Vertbbres, tome ii. p. 367); and in 

 1845, Bowerbank changed the generic name of " Spongia " to 

 " Verongia " (in honour of Dr. Veronge, who sent the speci- 

 men to him), adding the following diagnosis of its fibre, ac- 

 companied by equally good illustrations, viz. : — 



" Skeleton composed of a network of keratose fibres inoscu- 

 lating in every direction without order. Fibre cylindrical, 

 continuously fistular, without spicula. Cavity of the fibre 

 simple" ('Annals,' vol. xvi. p. 403, pi. xiii. fig. 7), whereby 

 Esper's " Spongia Jistularis " became Verongia Jistidaris, 

 Bowerbank. 



Meanwhile, in 1833, Nardo, in his classification of tlie 



