BATHYMETRICAL AND GEOGRAPHICAL 



DISTRIBUTION. 



The accompanying table (pp. 368 and 369) shows at a glance the princi- 

 pal features of distribution of the different zones of depth. We can dis- 

 tinguish a strictly littoral fauna, extending from tide-mark to generally less 

 than 10 fathoms, though a few of the species characteristic of this zone 

 extend to a depth of 34 and 40 fathoms. This fauna consists of 



Diadema setosum. 

 Echinoraetra subangularis. 

 Echinometra viridis. 

 Toxopneustes variegatus. 

 Hipponoe esculenta. 

 Echinanthus rosaceus. 



Clypeaster subdepressus. 

 Mellita testudinata. 

 Encope Miehelini. 

 Encope emarginata. 

 Echinoneus semilunaris. 

 Brissus unicolor. 



A second set of species, less numerous, extends from the shore to a much 

 greater depth, — from 80 to about 120 fathoms. They are 



Cidaris tribuloides. 

 Arbaeia punctulata. 

 Meoma ventricosa. 



Metalia pectoralis. 

 Moira atropos. 



At a depth of from 30 to 40 fathoms commences a third set of species, 

 the majority ranging to about 160 fathoms, though two species range to 

 270 fathoms (marked*), and a few species commence at a greater depth, 

 80 to 90 fathoms. These species are 



* Dorocidaris papillata. 

 Echinus gracilis. 

 Temnechinus maculatus. 



* Trigonocidaris albida. 

 Rhynchopygus caribaearum. 

 Ecbinolampas depressa. 

 Neolampas rostellata. 



Brissopsis lyrifera. 

 Agassizia excentrica. 

 Echinocardium flavescens. 

 Echinocardinm pennatifidum. 

 Echinocardium cordatum. 

 Schizaster fragilis. 



