GENEEA AND GEOUPS OF THE ECHINOIDEA. 311 



It is necessary, thanks to Prof. Bell's work, to make the fol- 

 lowing corrections : — 



PJiormosoma, p. 42, should be in a new subfamily of Echino- 

 thuridse. 



Therefore : — 



P. 40, 5 lines from bottom, after " a series of longitudinal 

 muscles " add " may exist or not ; " and 6 lines from bottom, after 

 " internal very large " add " or ill developed." 



P. 43, 14 lines from bottom, add " Internal longitudinal muscles 

 absent ; internal hrancTiicd small or rudimentary.'''' 



P. 44, 20 lines from bottom, add " Internal Iranchics large ; 

 internal longitudinal muscles developed''' 



P. 45, 13 lines from top, /or " Cyphosomidae " read " Cyphoso- 

 matidae." 



P. 207, 20 lines from top, expunge " Syn. Guettaria, Gauthier, 

 1887. Entomaster, Gauthier, 1887." 



Passim, for " Peron " read " Peron." 



M. V. Gauthier has obligingly sent me his generic descrip- 

 tions of Guettaria and Entomaster, which were not available 

 before the last sheet but one of this work was in the press. 



Genus Gfettaeia, Gauthier, 1887, Assoc. Frang. pour VAvanc. 

 d. Sci. (Toulouse), p. 528. 



This genus is allied to Cardiaster, and has a deep narrow 

 anterior groove actinally, with a sunken and almost circular 

 peristome in it ; the tubercles are larger than in Micraster, and 

 there is a posterior notch resembKng that of Hemipneustes. 

 There are two large pores besides the small tentacular pore in 

 each antero-lateral radial plate. 



Cretaceous : Africa, Tunis, and Madagascar. 



The genus Entomaster, Gauthier, 1887, op.cit. pi. xvi., appears 

 to be of subgeneric value, like Lampadaster, Cott. 1 place it 

 provisionally as a subgenus of Holaster. 



Cretaceous : Africa, Tunis. 



LINN. JOUEN. — ZOOLOGY, VOL. XXIII. 21 



