322 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



6° S. lat., while the Pauamic fauua is practically confined to the 

 shores north of that point. In spite of its low latitude the coast of Peru 

 south of Agnja Point is far from tropical, and the ruariue life is dis- 

 tinctly that of temperate seas, owing to the great Humboldt or Peruvian 

 current, which brings the cold waters of the antarctic region down nearly 

 to the equator.^ 



Of the fifty-four echinoderuis included in this report, twenty-one are 

 found onh^ on the less than two hundred miles of coast north of Aguja 

 Point, Avhile of the remaining thirtj'-three species only about a dozen 

 really characterize the succeeding shore line of over twelve hundred 

 miles. Some fifteen species occur both north and south of Aguja Point, 

 while the range of at least half a dozen species is practically unknown. 

 A more detailed analysis of the fauna brings out some of its most inter- 

 esting features and reveals the striking contrast between its two com- 

 ponents. North of Aguja Point the following twenty-two species have 

 been taken, none of which has yet been recorded from far south of there. 

 Those marked * are in the Coker collection. 



*Astropecten erinaceus *Ophiothrix magnifica 



fragilis * spiculata 



* peruvianus Gorgonocephalus panamensis 



*Luidia Columbia Arbacia stellata 



Nidorellia armata Echinoraetra van brunti 



Oreaster occidentalis *Encope micropora 

 Paulia horrida Mellita pacifica 



Phataria unifascialis * stokesii 



Ophioderma panamensis Lovenia cordiformis 



Amphiodia grisea *Agassizia scrobiculata 



Hemipholis gracilis *Thyone gibber 



Three of these species {Astropecten peruciamis, Anipliiodia grisea, 

 Ophiothrix magnifica) seem to have a very restricted range, as they are 

 not known from north of the equator, but the remaining nineteen species 

 are distinctly Panamic. To these nineteen should be added Pliaria 

 jiyramidata, the occurrence of which south of Aguja Point is open to 

 very serious question, and the single specimen of Mitlirodia hradleyi, 

 labeled " Arica," is not sufficient proof of its occurrence south of the 

 Panamic region. The new Luidia phragma probably belongs in this 



1 For an account of the characteristics of tlie Peruvian coast see Coker, Bull 

 Bureau of Fisheries, 1910, 28, pp. 335-340. 



