59 



ON THE FATPLECTELLA ASPEBOILLUM, Owen; 

 OR " VENUS'S FLOWER liASKET," 



A SPECIES OF SPONGE BELONGING TO TilE ALCYONOID FAMILY; 



AND 



A NOTICE OP THE UTALONEMA OR "GLASS ROPE" 

 SPONGE. 



By George Bennett, M.D., F.L.S., &o., Cork. Mem. of the 

 Royal Society of Tasmania. 



[Bead loth July, 1875.] 



Sponges assume a great variety of fonns, some are 

 cylindrioal and cu[)-sliaped, others are flattened, splicrical, 

 and linger shaped, varying in size from small specks to 

 gigantic dimensions, the latter exemplijfied in the so-called 

 " Neptune's Cup," (T/ialassejiia Ncptuni) a specimen of which 

 is in the Museum of the Society. Some of the sponges 

 disjday a great variety of rich colours, fx'om bright scarlet 

 and mauve, to pale yellow and rose, but the beautiful and 

 delicate tints change when exposed to the air to a dull 

 brownish hue. Sponges are formed of a soft glairy substance 

 termed sareode, which envelopes a skeleton composed of 

 silicious, calcareous, or horny material. The fii'st exemplified 

 by the Euplcctella, lli/aJoiiema, Tlolienia, Eossella, &c., &c. ; 

 the second by the genus Grautia, and the last by the common 

 sponge {Sponfjia communis) forming an elastic substance 

 extensively employed for domestic purposes. 



The most delicate and beautiful of the silicious sponges are 

 those composed of threads or filaments of almost pure silex, 

 beautifully interlaced and terminating at the base iu delicate 

 threads of exquisite fineness like spun silk, as seen in the 

 Eujylectella aspergillum of Owen, popularly named " Venus's 

 Flower Basket," resembling iu its form a bouquet holder of 

 spun glass ; others form hollow cups, from which beards of 

 long, flossy filaments are pendent, consisting of silex 

 resembling spun glass, as in Holtenia, Bossella, &c. Another 

 remarkable silicious sponge, is the Hyalonema, known as the 

 " Glass Coral," or " Rope Glass ;" this sponge or rather a 

 portion of it, I had an opportunity of examining in the 

 Museum of the Royal Society at Hobart Town, and also some 

 specimens in the possession of Mr. James Macfarlane, of that 

 city, who brought them from Japan, and ju-esented the 

 examples in the Society's Museum. The portions of the 

 Hyalonema I examined consisted of a rod of twisted fibres 

 varying in thickness, and about six or seven inches in length, 

 encased in a brownish leathery coating, the surface of which 

 wag studded with a species of parasitical Zoophyte ; the lower 



