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in its very young or larval condition, and finding its 

 quarters comfortable, dallied so long as to have outgrown 

 the dimensions of the portals whereby it entered. It was 

 originally represented by the Chinese dealers that the crab 

 was the fabricator of its extemporised silicious cage, and a 

 greater value being set upon those sponges which con- 

 tained a crustaceous occupant, they resorted to the practice 

 of skilfully removing the base of the sponge, introducing 

 a crab, and fastening it up again in such a manner that the 

 rupture made could not be detected. 



Among the notable species belonging to the same group 

 of silicious sponges have to be included the curious glass- 

 rope sponge {Hyalonenia), originally brought from the 

 Chinese sea, but since obtained from the deeper parts of 

 the Atlantic. The body of the sponge, as in many other 

 forms, is cup-shaped, but supported on a long stalk, con- 

 sisting of a twisted wisp-like bundle of long silicious 

 spicules that spread out basally in a brush-like manner, 

 and serve like a root, to anchor the sponge in the soft 

 slimy ooze that forms its habitat. A parasitic coral 

 {Palythoa) usually encrusts the elongate stalk of this 

 sponge, and these stalks, consisting of tiny glass-like 

 spicules invested by the coral, were at first alone dis- 

 covered and supposed to represent a complete organism, 

 the sponge body afterwards obtained being treated by 

 some authorities as a parasite. This error in the interpre- 

 tation of Hyalonema received additional support from the 

 circumstance that the Japanese divers, from whom the 

 first examples were obtained, supplied specimens which 

 they asserted to represent their natural growth, with the 

 top end inserted into stones previously bored by the 

 Pholas, and with the expanding brush-like end projecting 

 outwards. Closely allied to the glass-rope sponge are the 



