73 
in which the tubercles are of the same form, room x 
have some spines much longer than the rest 
(Echinometra ); as the Spiniferous Sea-Egg 
(Echinus lucunter ), the Triangular-spined Sea- 
Egg ( Echinus trigonarius ), and the Artichoke, 
or Black Sea-Egg ( Echinus atratus ), peculiar 
for the larger spines being very short and trunc¬ 
ated, forming a smooth surface, somewhat re¬ 
sembling a tessellated pavement. In other 
species which have the spines of an unequal 
size, the tubercles to which they are attached 
are pierced in the centre (Cidaris'). Some of 
these, which are of a spherical form, and have 
very narrow wavy rows of pores, are called 
Turbans, as the Imperial Turban (Cidaris impe- 
rialis) and the Porcupine Turban ( Cidaris hys- 
trix); while those which are depressed, with 
narrow separate rows of pores, are called Dia¬ 
dems. These often have tubular spines, as the 
common Diadem ( Echinus diadema ). 
Several of the species of the orbicular kind 
live in holes in rocks, and they are believed, by 
some authors, to have the faculty, like the Pid- 
dock (. Pholas ), of boring into their substance. 
On the wall, between the windows, are the 
horns of some species of Rhinoceros, and 
round the Room, over the Cases, are suspend- 
ed a series of the horns of various species of 
Deer ( Cervus ), as the Elk, the Roebuck, the 
Virginian and Mexican Deer, the Rein-Deer, 
the 
