ECHINUS. 126 



it generally lies motionless on the l>a.-e or tin- v.-rtez, according as it 

 fall* nn either. But SOUR- of the spines very soon begin to move, and 

 these are followed l>y the suckers. Evident exert ion is employed to gnin 

 :i suitable position tor the subject traversing its prison. If a portion of 

 food be now dropped into the vessel, the Echinus speedily becomes seu- 

 -iM' of it.s presence. Should the creature be above, the suckers extend, 

 ami its descent commences immediately, as it hastens to the repast. 



It i-i one of the most voracious and promiscuous feeders, always 

 ready to eat, nor is any animal better qualified for the destruction of 

 others with impunity to itself. The strength of the teeth is marvellous, 

 and, as if to prove auxiliaries, the principal power for the capture of 

 I 'ivy seems to reside in the suckers near the mouth. 



the most singular and complicated part of the dental apparatus 

 i* contained within. It is scarcely to be described, and can be inspected 

 only by sawing off a segment of the under part of the shell, which I have 



ailed the base. Then it is discovered to consist of so many parts, 

 operating by such complex movements, that I should despair of 

 [laiimij: the province and effects of almost the whole. The five cut 

 compounded as a large inverted cone, projecting below with its vertex 

 as a point beyond the level of the shell, destroy the hardest substances. 



-Plate XXXI. fig. 2, n. The pointed cutter, fig. 5, is lodged within 



hollow prisms, figs. 3, 4, as in a case. On inspecting the inside of 



the sundered segment, a vertical ring, consisting of five staples, is seen 



considerably elevated above the inner surface of the shell, surrounding the 



orifice of the mouth, into which staples various ligaments secure the bane 



of the inverted cone, fig. 7, a, a, a. The whole apparatus is represented 



along with a section around the mouth, fig. 6, a, a, a, being the upper 



ends of the teeth. ,/ .%/>// within the Echinus, and as in fig. 2, l>, b, b, b. 



Hut I repeat, that nothing short of actual inspection can convey an 



\planation of the operation of the various parts, and their action. The 

 -t met ure of the mouth of this animal offers a remarkable instance of 

 natural mechanism. 



These creatures often devour pure shelly matter, as appears from 

 the numerous pellets discharged. The fishermen U-lieve that they like 



