168 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



1858 he described the fossil Eocidaris. The same year (1858) 

 Quenstedt named Polycidaris and Leptoeidaris for fossil forms. In 

 1862 Cotteau described the remarkable fossil Orthocidaris, and the fol- 

 lowing year the equally interesting fossil Temnocidaris. In 1863, 

 A. Agassiz suggested the name Stephanocidaris for Lamarck's bispinosa, 

 and Prionocidaris for pistillaris. At the same time he proposed Chon- 

 drocidaris as a new genus for a notable species from the Hawaiian Islands, 

 and Gymnocidaris for metularia Lam. and a supposedly new species, 

 minor. He also proposed Orthocidaris and Temnocidaris as new genera 

 of recent Cidaridae, but later (1869) withdrew them as preoccupied by 

 Cotteau's fossil forms. At this later date he suggested Dorocidaris for a 

 new species, abyssicola, associating with it ajfinis Phil, and papillata Leske. 

 With the last Lamarck's hystrix is synonymous, and consequently, as a 

 result of these various changes, there remained in Lamarck's genus 

 " Cidarites : Turbans " only the well-known West Indian species, 

 tribuluides. 



In the "Revision of the Echini" (1872) A. Agassiz recognized only 

 six genera of the recent Cidaridae, as follows : — 



Cidaris Klein, with 3 species. (Including Gymnocidaris A. Ag.) 

 Dorocidaris A. Agassiz, with 1 species. (Including Orthocidaris A. Ag.) 

 Phyllacanthus Brandt, with 6 species. (Including Prionocidaris A. Ag., and 



Cliondrocidaris A. Ag.) 

 Stephanocidaris A. Agassiz, with 1 species. 

 Porocidaris Desor, with 1 species. 

 Goniocidaris Desor, with 3 species. (Including Temnocidaris A. Ag.) 



This classification has been maintained by Agassiz ever since, -without 

 any changes other than the addition of ten more species (1881, 1883, 

 1898) and the unique genus Centrocidaris (1904). 



In 1877 Studer described Schleinitzia as a recent genus allied to 

 Phyllacanthus. In 1883 Pomel divided the " Cidarides " into three 

 subfamilies, the Cidariens, Goniocidariens, and Rhabdocidariens. The 

 first contains four genera, including of Agassiz's six only Cidaris, which 

 is divided into five sections (subgenera 1 ) ; the second subfamily con- 

 tains four genera also, including Dorocidaris and Goniocidaris of Agassiz's 

 list ; the third contains seven genera, including the remaining three of 

 Agassiz, though Stephanocidaris is considered only a subgenus (?) of Phyl- 

 lacanthus. Although Pomel thus recognizes fifteen genera and six sub- 

 genera (?), his classification of the recent forms is essentially identical 

 with that of A. Agassiz. The new genera which he proposes are Tylo- 

 cidaris, Stereocidaris, Typocidaris, and Pleurocidaris, all for fossil 



