COMMON EGG-URCHIN. 



149 



ECHINIDM. 



CI DA RITES. 



\?-i.© -v 







«s 



'v.'v 1 .' .•.",■■■. v..-™ -■ 



la^HJjiSi ii jawfe -j. '^- ■.- 



"!*■■■ '''.'.7, rUIRWV-n- 



U ■ - — '"-■'i 



Genus Echinus. Linnaeus. 



Generic Character. — Body globose ; ambulacra continuous from mouth to 

 anus, which are both central, the former below, the latter above; spiniferous 

 tubercles imperforate ; spines of one form. 



THE COMMON EGG-URCHIN. 



SEA-EGG. SCa'aD MAn's HEAD. 



Echinus sphara. Muller. 



Specific Character. — Rows of pores obliquely parallel, three pairs of pores in 

 each row; spines thick, conic, longitudinally striate; striae broader than the 

 ridges, and transversely striated ; primaries scarcely longer than secondaries. 



Echinus mar inus, Lister, An. Ang. p. 169, t. iii. f. 18. Borlase, Corn. p. 



278, t. xxviii. fig. 27. 

 Echinus sphcera, Muller, Zoo]. Pan. Prod. 2845. Giuelin, .'Slfifl. 



