IS I 



ROBERT TRACY JACKSON ON ECHINI. 



213 



212 



TEXT-FIOS. 207-216. Essential features of the lantern in representative Echini. In each species figured are shown a 

 pyramid with associated parts in place seen in face view, with a cross section of the tooth; also an epiphysis (A) seen from 

 above, and a top view of a half-pyramid (B) from which the epiphysis has been removed. 



207. Pholidechinus brauni sp. nov. Lower Carboniferous, Crawfordsville, Indiana. Yale University Museum Coll., 

 321. X 3.4. (Compare Plate 27.) Tip of compass restored as indicated by dotted lines. Tooth grooved and epi- 

 physes narrow, foramen magnum moderately deep. 



208. Archaeocidaris rossica (Buch). Lower Carboniferous, Miatschkowa, Province of Moscow, Russia. Mus. Comp. 

 Zo6l. Coll., 3,181. X 3.2. (Compare Plate 12.) Top of pyramid smooth, tooth grooved, epiphyses narrow, foramen mag- 

 num moderately deep. Tip of the tooth restored as indicated by dotted lines. 



209. Goniocidaris canaliculata A. Agassiz. (Adapted from Plate 2, fig. 17.) Young lantern, epiphyses narrow, fora- 

 men magnum moderately deep. 



210. Eucidaris tribuloides (Lamarck). Bahamas. R. T. J. Coll., 694. X 3.2. Top of pyramid smooth, tooth 

 grooved, cpiphyses narrow, foramen magnum very shallow. (Compare text-fig. 218, p. 191; Plate 2, figs 7-16.) 



