170 



I'ANAMIC DEEP SEA ECHINI. 



oculars occupy notches in this central plate. The apical system is also very 

 similar to that of Phrissoej/stis aculeata, Fig. 276, of Argopatagus, Fig. 252, 



ami llomolampas, Fig. 258; in 

 Palseotropus there are, however, 

 only three genital pores. 



Fig. 245. Pal>eotropi s Loveni 



~'.\ mm. 



Fig. 246. Pal-eotropus Loveni. 



Koehler 1 has called attention to the relations of P. Hironddlei to the 

 other species of the genus. We may add the following to his notes. 



Fig. 247 



PaI-^OTBOPUS JosKl'lux.E. 

 After Loveni. 



23 iiiiii. 



Fig. 248. PAL^OTRortrs Loveni 



Palceotropus Hironddlei Koehler" differs from P. Josephines 8 and P. Loveni 

 by its coarse tuberculation, the splitting up of the central plate into its 



1 Campagnea Scientifiques du Prince de Monaco. Fasc, XII. Echinides et Ophiures dn Yacht 

 l'Hirondelle, par R. Koehler, 1898, p. 29. 



2 Koehler, loc. cit. Pis V, figs. 12-14; VI, figs. 27,28. 



8 Koehler inadverently mentions /' Josephina as described by me. It should he referred to 

 Loven, who established tin' genus, ami who described the first species of the genus; Loven, Etudes, 

 p. 17, PI. XIII, tigs. 108-113. 



