Sponges from South Australia. 3G7 



gin, Spiculation that of Echinonema anchoratum (' Annals,' 

 1881, vol. vii. p. 379), viz. : — 1, smooth acuate, 25 by 

 f-6000ths, chiefly confined to the centre of the fibre, with 

 grains of sand and foreign objects ; 2, echinating spicule, a 

 spiniferous acuate, 16 by 1- 6000th ; 3, flesh-spicule a navicu- 

 liform equianchorate confined to the sarcode, 3-g-6000ths. 

 Structure compact throughout, without axial or central con- 

 densation. Size of specimen, which is wet, 7 in. high by 

 7 X -g- in. horizontally. 



Depth 6 fath. 



Ohs. There is also a diy specimen of this species 10 in. 

 high by 9 X 5 in. horizontally, composed of a large group of 

 flabelliform plicated lobes of diffei-ent sizes below the single 

 one above mentioned, more or less proliferous and twisted in 

 form, some of which are anything but like the typical one 

 above described, yet all evidently modifications of the same 

 plan, rising and spreading into a great group florally from a 

 contracted subsessile base, about 2-^ in. in diameter. 



It is this specimen which I have briefly described in the 

 ' Annals ' of 1885 (vol. xv. p. 320) mider the above name, 

 and of which there are several others of a like kind in the 

 British Museum, all of which come from the south coast of 

 Australia, and bear my running no. " 128." As spouges on 

 being dried genei-ally shrink up to half their natural size, the 

 dried one just mentioned must originally have been twice 

 that above stated, so that when fresh it must have been a still 

 more magnificent specimen than it is at present. The genus 

 has been named after Mr. J. Bracebridge Wilson, M.A., 

 F.L.S., of the Church of England Grammar School, Geelong, 

 Victoria colony, South Australia, to whom, as before stated, I 

 am indebted for all these sponges, both wet and dried. 



Plumohalichondrina Aeenacea. 

 39. Plumohalichondria arenacea. 



Irregularly club-shaped, sessile, massive, lobed, tall, high, 

 enclosing shells and sand at the base, which is contracted. 

 Consistence tough, firm, resilient. Colour when fresh not 

 mentioned, now pale yellow throughout. Surface uniformly 

 granulated, covered by a minutely reticulated dermis. Vents 

 rather small, scattered over the surface generally. Spicules 

 of three forms, viz. : — 1, skeletal acerate (the tibiella) nearly 

 straight, 40 by l^-OOOOths, chiefly confined to the centre of 

 the fibre, with grains of sand and foreign objects ; 2, spined 

 acuates more or less bent, of different sizes under 32-6U00ths 



25* 



