374 HAWAIIAN AND OTHER PACIFIC ECHINI. 



reasons for not accepting the new genus proposed by Doderlein, of which oblonga 

 is the type are given above (p. 367). The series of specimens at hand is most 

 perplexing, so great is the indi\'idual diversity shown. On the one hand, there 

 are from Clarion Island, black specimens \vith high, compressed test, big abacti- 

 nal tubercles, and small abactinal system with all the oculars completely ex- 

 cluded from the periproct, but with spines tapering to a point and not nearly as 

 thick as they should be in oblonga. And on the other hand there are specimens 

 from Makemo in the Paumotus, which have the characteristic spines of oblonga 

 but show a remarkable diversity in color; some are deep purple, some graj-ish 

 lavender, and one is dull purplish red. In the presence of these puzzling 

 specimens, much sympathy is felt with de Meijere's remark, apropos of 

 oblonga, " Dass letztere eine gute Art ist, glaube ich kaum." 



Mortensen first called attention to the curious fact that the globiferous 

 pedicellaria) of oblonga have a jointed stalk. Examination of a considerable 

 amount of material shows that this peculiarity exists in less than half the globif- 

 erous pedicellariae; at least, more than half of those examined did not show it. 

 Such a joint in the stalk of the pedicellariae is not known in an}' other echinoid, 

 although it is easy to see how it might be of real use. 



The " Albatross" obtained specimens of oblonga from the following stations: — 



Laysan, Hawaiian Islands. Hilo, Hawaii, H. I. 



Necker Island, H. I. Puako Bay, Hawaii, H. I. 



Lanai, H. I. Rangiroa, Paumotu Islands. 



Kamaliiia Bay, Niihau, H. I. Makemo, Paumotus. 



Ilnnalci, Kauai, H. I. Fakarava, Paumotus. 



Waianao, Oahu, H. I. Clarion Island, Mexico. 



Honolulu Hoof, Oahu, H. I. 

 Sixty-soven spooimcns. 



Echinometra insularis,' sp. nov. 



Plates 95, figs. 13-15; 114, figs. 3, 4- 



On first examination the Echinometra^s from Ea.'^tor Island showed considcral)lc 

 resomblanro to Van Brunti, but furtlior study soon proved that they are more 

 nearly related to Mntluri. The test is rather wide and flat, the width being 

 .85-. 95 of tiio longtli and tiie heigiit about half the length or a trifle less. The 



> Itutiiaris = portaining to an island. 



