dredged up from Bass's Straits. 375 



p. 32) ; and among them Dr. Bowerbank noticed one almost 

 identical with Dysideafragilis^ Johnston, to which he gave the 

 name of '•'■Dysidea Kirhii'''' {ibid. p. 63, pi. vi.). This species 

 in structural composition appeared to Dr. Bowerbank to be, if 

 any thing, still more arenated than D. fragilis \ thns he states, 

 " in D. fragilis^ Johnston, the primary fibres are often as abmi- 

 dantly arenated. as those of the Australian species, while the 

 secondary ones are only partially filled with extraneous 

 matter ; and in this condition they are more or less tubular " 

 (Brit. Spongiadffi, 1864, vol. i. p. 212). After this, viz. in 

 1874j Dr. Bowerbank gave some very good representations of 

 Dysidea fragilis from specimens now in the British Museum, 

 which I have examined, but, as they appear lolien dry and 

 washed out upon our heach {pp. cit. vol. iii. pi. Ixix.). 



Now Col. Montagu, in 1812, who appears to have first 

 noticed this sponge on the " south coast of Devon," called it 

 Bpongia friahilis (Wernerian Mem. 1818, vol. ii. p. 114, 

 pi. xvi. figs. 1, 2), wdiicli Johnston, who states that Mon- 

 tagu's account was " read to the Society on the 9th March, 

 1812" (Hist. Brit. Sponges, 1842, p. 37, footnote), changed 

 generically to '"'' Dysidea ; " so that, besides having examined 

 Dr. Bowerbank's type specimens now in the British Museum, 

 1 am living on the coast where ^Montagu found the original 

 specimens ; and, so far as the dead and " dried form washed 

 out on the beach " goes, the descriptions and delineations 

 respectively are accurate ; but not so as regards the appearance 

 of this sponge while growing in situ on the rocks ; for there it 

 is almost identical with the representation of Spongelia in- 

 crustans given by Schmidt (Spong. Adriat. Meeres, Taf. iii. 

 fig. 7) . Schmidt himself has identified Dysidea fragilis with 

 Spongelia^ Nardo {op. cit. 1866, 2nd Suppl. p. 11), but pro- 

 visionally^ because he had only seen one of the " dried " and 

 washed-out specimens to which I have alluded. It seems to 

 me therefore that Montagu's Spongia friahilis of 1812 is 

 Johnston's Dysidea fragilis of 1842 and Nardo's Spongelia of 

 1847, of which the best representation in the free state that I 

 have seen has been given by Prof. F. E. Schulze of Spongelia 

 pallescens (Zeitschrift f. wiss. Zoologie, Bd. xxxii. Taf. v. 

 fig. 2) , the slight variation in appearance between Spongelia 

 pallescens and ^S*. incrustans here being of no consequence. 



To return to Dysidea Kirhii , Bk., I cannot see much 

 difference in stiucture between it and Dysidea fragilis, both 

 with and without the sarcode ; but in general form, colour, 

 and perliaps in the form of the points {conidi) on the surface 

 being less prominent, it differs, as will have been seen by the 

 above description. 



28* 



