170 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



Stereocidaris Pomel, 10 species. 



Goniocidaris Desor, 4 species and subgenus Discocidaris Doderlein, 3 species. 



Petalocidaris, g. n., 1 species. 



Phyllacanthus Brandt (emend.), 3 species. 



Histocidaris, g. n., 1 species. 



Porocidaris Desor, 1 species and 1 variety. 



Genus undetermined, 12 species. 



Total, 56 species and 1 variety. 



Of these 56 species, seven, and the one variety, are described for the first 

 time, but only one of them is figured. Unfortunately Mortensen was 

 handicapped by lack of material and the apparent necessity of not de- 

 nuding even in part the specimens which were available, and as a conse- 

 quence his descriptions are, with one exception, incomplete, and in several 

 cases quite inadequate. Good photographs of his types would be a very 

 great help in recognizing these supposedly new species. 



In 1906 Doderlein presents his classification of the recent Cidaridae, 

 the result of more than twenty years' study of the family. It is radically 

 different from his earlier (1887) arrangement, not merely because no 

 reference is made to fossil forms, but because he endeavors to make use 

 of Mortensen's principles, which his own observations often contradict * 

 and his judgment not infrequently condemns. 2 This latest arrangement 

 of the family is as follows : — 



Cidaris Leske (syn. Dorocidaris A. Ag.), 4 species. 



Tretocidaris Mortensen, 3 species. 



Cidarites Lamarck (syn. Cidaris emend. Mortensen). 



Subgenus Dorocidaris A. Ag., 4 species. 



Gymnocidaris A. Ag., 3 species and 1 variety. 

 Stephanocidaris A. Ag., 5 species and 7 varieties. 

 Chondrocidaris A. Ag., 1 species. 

 Goniocidaris L. Agassiz et Desor. 



Subgenus Goniocidaris s. str., 6 species. 

 Discocidaris Dod., 6 species. 

 Stereocidaris Pomel, 14 species. 

 Acantliocidaris Mortensen, i species. 

 Phyllacanthus Brandt, 1 species and 3 varieties. 

 Histocidaris Mortensen, 2 species. 

 Porocidaris Desor, 1 species and 1 variety. 

 Genus undetermined, 6 species. 

 Total: 10 genera, 5 subgenera, 57 species, and 12 varieties. 



i Compare page 102, line 24, with page 106, lines 34-36 and page 109, lines 20-21. 

 2 See p. 93 et seq. 



