so7ne Species referred to it. 61 



part o£ April 18-48." The trivial name " kei/serlingl " is 

 therefore the one to be adopted. 



We have now to enquire in what genus Cidaris keyserlingi 

 should be placed. That it cannot be Eocidaris or Archceo- 

 ci'daris {■= Ec}dnocrinus) has been urged above. Professors 

 Clark and Jackson, as intimated in my opening paragraphs, 

 would refer it to Cidaris, while Mr. Lambert (April 1899, 

 p. 82) has made it the genotype of Eotiaris. The former 

 course seems to me to ignore important structural differences, 

 while the latter course lays undue stress on a very trifling 

 feature. In the ' Triassic Echinoderras o£ Bakony,^ I have 

 referred Cidaris heyserlingi to Doederlein's genus Miocidaris. 

 This genus also is regarded by Professor H. L. Clark as 

 indistinguishable from Cidaris, an opinion with which I 

 cannot agree. 



Miocidaris, ITS Species and Structure. 



Since Miocidaris is fully discussed in the ' Triassic Echino- 

 dernis of Bakony/ from the nomenclatoral, anatomical, and 

 faunistic standpoints, the conclusions there reached need but 

 a brief summary here. On the other hand it has now become 

 necessary to give reason for the distinction of Miocidaris 

 from Cidaris. 



^7?oci(fan's was established by L. Doederlein in 1887 (p. 40), 

 and from among the species referred to it by liim I have 

 selected as genotype Cidaris hlipsteini, interpreting that to 

 moan C.kUpsteiniV)^s>oxl^d^, non Marcou 1847. Since a new 

 name is needed for this species, I propose Miocidaris cassiani, 

 attaching thereto as lectotype the interambulacral fragment 

 figured by Klipstein (1843) in plate xviii. fig. 15, and now 

 in the Britisii Museum (regd. .36512). 



With Lambert (1900) I remove Cidaris siihnobilis to 

 liiadoddaris, but include in Miocidaris the species Cidaris 

 suhcorouata, which Doederlein placed in an unnamed section 5. 



It is probable that various species from the older Jurassic 

 ro( ks, such as Cidaris amalthei and C. arietis included by 

 Doederlein, belong to Miocidaris; but I have not personally 

 examined the type-specimens. 



The interambulacrals from the Wellen-dolomite of the 

 Schwjirzvvald wiiich Quenstedt (187.5, pi. Ixvii. fig, 115) 

 referred to Cidaris grandceva are to be placed in Miocidaris. 

 So also is the specimen from Kirchberg on the Jaxt, whicli is 

 the holotype of Cidaris coceva Quenstedt (1875, p. 160, 

 pi. Ixvii. tig. 110) ; this is No. 4254 of Tubingen Geo- 

 logical Museum, and I owe the opportunity of examining 

 it to the kindness of Professor Koken and Dr. F. von Huene. 



