"WONDERS OF SPONGE 6TKTJCTUKE. 11 



So, when such an extraordinary combination was found 

 as a bundle of long glassy threads, pressed together with 

 a membranous wrapper, and stuck into a sponge at one 

 end and a lump of coral at the other, there 'was good 

 justification for considering it as a mere piece of Japanese 

 ingenuity. The constituent parts were evidently what 

 they appeared to be. The sponge was certainly a sponge; 

 no one could doubt the genuineness of the coral; the 

 investing membrane was of an animal nature, and the 

 wisp of long threads was certainly glass, its siliceous 

 nature being ascertained by chemistry. A definite name 

 was then given to it, Hyalonema, i.e. Glass-rope, and it was 

 admitted to be a natural production. 



By degrees additional specimens were discovered, but 

 without the coral, as shown in Fig. 1. The coral was 

 then seen to be a mere addition by way of improving the 

 look of the specimen; but the glass threads still remained 

 a mystery. 



All this time the savants were battling about the true 

 origin of the Hyalonema, some saying that the glass-wisp, 

 envelope, and sponge were formed from coral; others 

 that the glass-rope was formed by the sponge, and that 

 the envelope was a "commensal polyp." Commensal, I 

 may here explain, may be translated by the word " mess- 

 mate," and in zoology it signifies a parasite which feeds 

 with, but not upon, the being to which it is attached. 

 This was a very close approximation to the truth, the 

 envelope being, in truth, a mass of commensal polyps, 

 which, when dried, shrivelled up into the thin, leathery 

 membrane which had for so Ions; been a mystery. 



