i 



the Morphology of the Blastoidea. 245 



existence. Blastoids also seem to occur in the Lower Devo- 

 nian of France; for the Belocrinus Cottaldi, Mun.-Chalm., of 

 which QElilert has recently given a good figure *, appears to 

 us^ to be nothing but the elongated basal cup of a Troosto- 



crimes or Pentremitidea. It appears to be different from that 

 of any Crinoid. 



Locality and Horizon. Colle, near Sabero, Province of 

 Leon, Spain ; Lower Devonian. 



< 



Genus Troostocrinus, Shumard, 1865. 





Troostocrinus hispanicus, sp. nov. 



Spec. char. Calyx subfusiform and elongated, but less so 

 towards the base than in some other species of the genus. 

 Basal cup conical, with shallow re-entering angles in its upper 

 edge, while its sides become compressed and flattened below. 

 Radials long and narrow, twice the length of the basals, and 

 about equally divided into body and limbs ; the interradial 

 sutures comparatively straight and - almost parallel. Radial 

 sinuses narrow and sublinear. Ambulacra slanting sharply 

 down from the summit and gradually decreasing in width, 

 with the side plates projecting above the margins of the 

 sinuses, and at least twenty-five in number on each side ; the 

 median food-grooves very well defined. Orals exceedingly 

 minute and quite apical. Spiracles, peristome, and ornamen- 

 tation not preserved. Total height of calyx 25 millim. 



Obs. Although the specimen just described is but imper- 

 fectly preserved, it is one of unusual interest, as it affords 

 the first satisfactory indication of the presence of Troosto- 

 crinus in European rocks. 2\ hispanicus is a much more 

 robust species than T. Reinwardti 7 the type of the genus, 

 having larger, wider, and more 'expanding ambulacra than 

 occur in that well-known form. The summit is also more 

 spacious and more truncated than the corresponding part of 

 T. Reinwardti. The Spanish fossil may be distinguished 

 from T. bipy ramidalis } Hall sp., by its shorter ambulacra and 

 fewer side plates, together with the greater elongation of the 

 calyx from the radial lips downwards. The proportions of 

 T. subtruncatus, 

 are quite different 



Hall sp., and of T. Grosvenori, Shumard, 

 t from those of T. hispanicus. Perhaps on 

 ter agrees better with T. JVortkeni } Hall sp., 

 than with any of the species just named, except that its 

 ambulacra are broader. They are relatively longer than those 



* M Crinoides nouveaux du D6vonien de le Sarthe et de la Mayenne," 

 Bull. Soc. G4ol. de France, 3 e efirie, t. x. p. 362, pi. ix. tig. 3. 



