76 SVEN LOVEN, ON THE ECHINOIDEA DESCRIBED BY LINN.-ELS. 



doubt aboiit tlie genus, and the description enables us to de- 

 sio-nate very nearly the modern spccies it means. The cha- 

 racters taken from the zonae and the peristome are both pre- 

 sent in Boletia and Tripncustes, and in no other genus. But 

 LiNN.EUS never could have applied the terms: »hemisphoirica 

 sed magis o:ibba:> to a Boletia, nor would he have overlooked 

 its concavated basis. In that gen vis also the pores are not 

 very clearly »triplicate». To Tripneustes Ag., therefore, we 

 are led, to that group within the great genus Echinus v^^hich 

 was distinguished already by Blainville as his section G *), 

 and after him by Desmoulins as section F-). This last-named 

 author alone has ;^E. Gratilla L.?» as a doubtful synonym 

 under the E. fasciatus Lamck. This species, however, which 

 Desmoulins besides indicates as unknown to him, is charac- 

 terised Dy Lamarck"*): ^fasciis quinqueporis indivisis» and conse- 

 quently must be here discarded. 01" the remaining species of 

 Tripneustes the West Indian T. esculentus Leske does not 

 answer to the Linnean description; its general form is not 

 »hemisphserica, gibbav, the disks of the areai are mostly not as 

 conspicously »loeviores^^ as in other species. Neither can the 

 median pedicellar pores be said to answer to the words of 

 the description, that each zone consists of three series of pores, 

 each series bcing a longitudinal row of geminous perforations, 

 because in T. esculentus the inner row alone is regular, the 

 oviter one nearly so, but the middle one very irregular. It is 

 among the species described inhabiting the Indian Ocean and 

 the Pacific, that one in particular fully answers to the Linnean 

 description, the species common at ]\Iauritius, Zanzibar, Kee- 

 ling Island etc, which Blainville in 1825 named Echinus 

 inflatus. 



If after the examplc of Alexander Agassiz, who unites 

 them all into one species called Hipponoe variegata Leske, 

 the forms inhabitino- the seas of the old world, distino-uished bv 

 Lamarck and doubtino-lv admitted bv Blainville and Louis 

 Agassiz, are regarded as only nominal, the synonymy becomes 

 chieflv as follows: 



') Diet. se. nat. XXXVII, p. 91. 



-) Etudes, p. L^88. 



3) Hist. An. s. Vert., III. p. 45. 



