56 PROCEEDINGS OF THE ACADEMY OF [Vol. LXXIV 



Emoda H. and A. Adams. Type (now chosen) H. silacea Morelet 

 (1849). Cuba. 35 



In this group the radulae of the type species 36 , S. sagraiana 

 (d. Orbigny) (1845) 37 , and S. ciliata (Poey) (1852) 38 were examined. 

 The radular formulae of all three are included in Table III, but 

 only the first is figured (Plate IV, fig. 16; Plate V, fig. 19). 



The centrals are Alcadia-like as are those of Schasicheila s. s. 

 The A-central has a peculiar outer plate, which fits under the 

 C-central. The accessory plate is comparatively smaller than in 

 any of the preceding groups, but is heavy and has a strong lobe 

 for clasping the end of the comb-lateral. The latter is large and 

 heavy, with spatulate cusps, and a heavy, squarish base. There 

 are fewer cusps (6) in S. ciliata than in the other two species. 

 The inner marginals are bicuspid. In sagraiana and silacea, the 

 inner 4 or 5 have only two functional cusps, while in ciliata from 

 6 to 7 are functionally bicuspid. The difference between this 

 statement and the formulae, as given in Table III, is due to a small 

 vestigial tooth that appears quite variable in its occurrence. The 

 marginals are peculiarly heavy and wooden, like those of Schasi- 

 chelia s. s., and are not very numerous for such large shells. S. 

 ciliata has a smaller number of marginals than the other two. 



The shells of this group are amongst the largest and heaviest 

 of the entire family. In external appearance, they resemble those 

 of Analcadia, but the radula is distinctly Schasicheila-like, as is 

 also the sculpture of such species as S. ciliata. The latter probably 

 belongs in a different section than do the other two species. The 

 close relationship between Emoda and Schasicheila s. s. presents 

 additional evidence for the former land connection between Cuba 

 and Yucatan. 



Subgenus SCHASICHEILA s. s. Mexico, Guatemala. 



Schasicheila Shuttleworth (1852). Type (Fischer) S. nicoleti Sh. 

 (1852). Mexico. 



Schasichila and Schazicheila auct. 

 S. alata (" Menke"Pfr.). (1848). Cordova, Mexico. 



»S. pannucea Sowerby (1866), non Morelet. 

 S. fragilis Pilsbry (1899). Diente, Nuevo Leon, Mexico. 



35 As this group is used by Wagner (1907) in an emended sense, it was thought 

 best to choose a type from those of the species of H. and A. Adams, which are 

 also included by Wagner. 



36 2 alcoholic specimens; A. N. S. P. no. 110833; collected at Tabajo, Yunquede, 



Baracoa, Cuba, by Chas. T. Ramsden. 



37 3 alcoholic specimens; sent me by John B. Henderson; from western Cuba. 

 38 1 mounted slide from the collection of A. N. S. P.; made by A. P. Brown. 



