OCULAR AND GENITAL PLATES. 



153 



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605 Echinus aiRnis 

 20(1 Et'hinus csculcntus 



2,100 Arbacia punctulata, 

 Woods Hole 



170 Strongylocentrotus lividus 



159 Echinomctra inathaci 



100 Kchimis angulosus 



2(3 Salcnocidaris varispina 

 1(J4 Echinus niagcUanicus 



.■(78 Ecliinomctra lueuntcr, 



West Indies and Florida 



17.5 Ecliinomctra lucunter, 

 Bermuda 



5.5 Strongylocentrotus fragilis 

 76 Echinomctra van brunti 



2,700 Strongylocentrotus drobach- 

 iensis, York, Maine 



1,013 Toxopueustes variegatus 



120 Strongylocentrotus purpuratus 



1,463 Toxopneustes atlanlicus, 



Bermuda (45-60 mm. diam.). 



455 Tripneustes esculentus, 



West Indies and Florida 



246 Arbacia nigra 



1,168 Ccntrechinus setosus 

 12 Ccntrostcphanus rodgersi 



849 Eucidaris tribuloides 



12 Phj'llacanthus annulifera 



106 Phyllacanthus baculosa 

 47 Aspidodiadema nicobaricum 



