ECHINODEIIMATA. 



Fig. 49.— figure of spine of 

 echin'us— segment of section. 



hundred and twenty pores ; but as each sucker occupies a 

 pair of pores, the number of suckers would be half that 

 amount, or one thousand eight 

 hundred and sixty. Nor is the 

 structure of these animals less 

 complicated in other respects. 

 The shell is made up of above 

 three hundred pieces of one kind, 

 and nearly as many of another, 

 all dove-tailing together with the 

 greatest order and regularity, 

 bearing on their surfaces above 

 four thousand spines ; nay, if we 

 cut any individual spine into 

 slices and examine it with a 

 microscope, it will be seen to 

 present a pattern peculiar to the 

 si)ecies, and far beyond the reach 

 of art in its elaborate beauty 

 (Fig. 49). Truly the skill of the 

 great Architect of naturae is not 

 less displayed in the construction of a Sea-Urchin than 

 in the creation of a w^orld ! 



The eggs (or roe) of the EchiniLs are looked upon in 

 some countries as affording a very excellent dish, and we 

 find that among the Romans they were accounted deli- 

 cacies. It is recorded that they formed the principal dish 

 at the famous supper of Lentulus, when he was made 

 Flamen Martialis, or priest of Mars ; and Sea-Urchins are 

 still caught in great numbers upon the shores of the 

 Mediterranean, for the sake of their roe. 



The Sea-cucumbers ( Ilolotlmrice)^' (Fig. 50). The fisher- 

 man's di-edge occasionally brings up, on our own coasts, 

 slimy creatures, bearing no slight resemblance to a disagree- 

 able-looking cucumber, whence they aro commonly kno-uTi 

 by the name of Sea-GherJcins or Sea-Cucumhers. It is in 

 tropical seas, however, that these animals most abound, 

 where they lie in the mud or shallows, or crawl over the 

 coral rocks. The sm'face of their bodies is composed of a 

 dense, tough, leathery skin capable of being dilated or 

 contracted, lengthened or shortened at the will of the 

 animal. No stony shell is dej^osited uj^on their bodies ; 



bXod6vpiov, holotbom-ioD, a name ajiphed by Aristotle. 



