Sponges from South Australia. 281 



Thus, while the facts may be still fresh in the memory of 

 those who have read my report on the colltction of marine 

 sponges from Japan &c. ('Annals,' 1885, vol. xv. p. 387), 

 it might be observed that the polychotomous Chalina there 

 referred to (p. 402), although possessing the same form of 

 spicule as a similar species from the Mauritius, is a hand fide 

 solid, branched, and stipitate Chalinoid form characteristic of 

 my group " Digitata," while that from the Mauritius is an 

 Isodictyal Chalinoid form, in which the skeletal spicule is not 

 only larger, hut accompanied hy a minute acerate flesJi- spicule. 

 Hence, while the latter retains the proposed designation, viz. 

 " mauritiana^'' the former, for distinction's sake, might be 

 designated ^'■japonica.'''' (This, however, must bCjConsidered as 

 an ex post facto statement, since I was not made aware of the 

 presence of the flesh-spicule until after I had first written the 

 passages to which I have referred.) 



Now the Mauritius specimen (that Mr. B. W. Priest kindly 

 submitted for my examination, which, with a true Chalina- 

 like form, consisted only of a fragment about 3 inches long 

 and half an inch in diameter), presents on one side a flat sur- 

 face by which it had adhered to a mass of Nullipore on which 

 it had been growing ; and thus the sp ^cimen bears the same 

 relation in this respect to a solid, digitate, erect Chalina of 

 the British seas, that is C. polychotoma, that the latter does to 

 our British Halichondria siimdans^ Johnston (pi. viii.),= 

 Isodictya simulans, Bk. (Mon. vol. iii. pi. li. figs. 5 and 6) , 

 which, although occasionally rising up more or less into a 

 Chalina-like branched stem^ as frequently creeps in this form 

 over the surface of the rocks on which it may be growing (see 

 Johnston's illustrations, I. c.) ; but in the Mauritius specimen, 

 as before stated, the skeletal is accompanied by a flesh-spicule. 

 In short the spiculation of the Mauritius specimen consists of 

 a large sausage-like form witli several smaller ones in various 

 stages of development chiefly about the angles of its reticu- 

 lated structure ; and a minute, sharp-pointed, fusiform, acerate 

 flesh-spicule, chiefly arranged like a row of swallows on a 

 telegraph-wire, along the course of the large spicule or spicular 

 reticulation; while also, as before stated, the Japan specimen 

 only presents one form, viz. the sausage- shaped one, which is 

 much smaller, as may be seen by my illustrations (' Annals,' 

 I. c. pi. xiv. figs. 12 and 13). 



Again, in Dr. Bowerbank's representations of his Chalina 

 oculata (Mon. vol. iii. pi. Ixvi.) and that of his ^'■Isodictya 

 varians " {ih. pi. Ixxxviii.), the former from a specimen from 

 the open sea in the English Channel off Hastings, and the 

 latter from one from the mouth or estuary of the Mersey at 



