102 



ZOOLOGY. 



to Rhizocrinus, and was dredged in the Bay of Biscay o. 

 the depth of 2435 fathoms. B. Aldrichianus occurred in 

 1850 fathoms, latitude 1 47' X., longitude 24 26' W., off 

 the coast of Brazil. With it and also near the Crozet 

 Islands occurred the interesting Hyocrinus BetJiellianus 

 AVyville-Thompson, which bears in some points resemblance 

 to the palaeozoic genus, Platycrinus. 



Fig. 64. a, Pentacrinm cajwt-medusce, half natural size: b calyx-disk seen from 

 above, natural size.-^From Brehm's Thierleben. 



The most widely distributed species is the Rhizocrinus 

 lofotensis of Sars (Fig. 65), which is closely related to the 

 Bourguetticrinus of the chalk formation, and forms the 

 transitional type connecting the ApiocrinidcB with the 

 free-moving, unstalked Antedon. It occurs at the depth of 



