70 
ROOM XI. 
Nat. Hist. 
No. 14. Gorgonia—Eunicea, and Funiculina. 
No. 15. Plexaura—Muricea, and Antipathes. 
No. 16. Antipathes — Cirrhipathes—Hyalonema*, 
{Gray) —Virgularia — Pavonaria —Pennatula — Vere- 
tillum—Renilla — Briareum — Lobularia —Ammothea 
— Xenia — Neptoea — Aiithelia — Alcyonium — Cydo- 
nium — Pulmonellum — Massarium —Cliona. 
The sponges resemble the corals of the last family in 
various particulars, but their animal nature is not distinctly 
made out; those found in collections are merely the 
skeletons of the living mass, entirely destitute of the 
gelatinous portion which constitutes the animal, if it be 
really of that nature. Some naturalists have considered 
these skeletons, or Sponges, as analogous to the stems of 
Antipathes, or Black Coral, and consequently the axes of 
zoophytes; and have fancied that, when alive, they were 
covered, like the Antipathes, with a perishable crust, in 
which they supposed the polypes to be situated. But 
recent observations on them in their living state have 
not verified this theory; for they have been found to 
be entirely destitute of any polypi, and mere living 
masses, covered with a gelatinous coat, and absorbing 
water through the small pores spread over their surface, 
and emitting it by the larger scattered holes called 
oscula; and though the fibres of many of the sponges 
greatly resemble the axes of the Gorgoniae, in their 
chemical composition and organic structure, they 
nevertheless cannot be confidently pronounced to 
belong to the animal, rather than to the vegetable 
kingdom. The sponges are contained in the Table 
Cases, Nos. 17— 21. 
The Corallines were formerly considered as animals, 
* The axis of this extraordinary production, which Mr. Gray has 
named Hyalonema, or Glass Rope , is formed of numerous transparent 
siliceous fibres, slightly twisted together so as to look like a rope of 
spun glass; the fibres appear to be somewhat similar to the cal¬ 
careous spicula of the Alcyonia. These corals are found with their 
tapering base inserted in a sponge, on the coast of Japan. No 
animal, hitherto discovered, except the inhabitant of this curious and 
beautiful substance, is known to secrete pure silica. 
but 
