518 Verrill and Bush — Marine Mollusca of the Bermudas. 



Family CRASSATELLID^. 



Crassatellites (Crassinella) lunulata (Conrad), var. parva (C. B. Adams). 

 Plate LXIII. Fig. 11. 



Thetis parva C. B. Adams, Proceedings Boston Soc. Nat. Hist., ii, p. 9, Jan., 



1845. 

 Crassatella Gaudalupensis d'Orbigny, L'lle de Cuba, ii, p. 289, Atlas, pi. 



xxvii, figs. 24-26, 1853. 

 Astarte lunulata Conrad, Journ. Acad. Nat. Sci., Philadelphia, vii, p. 133, 



1837 ; Fossils of the Medial Tertiary of the United States, p. 44, pi. 21, f . 



8, 1840. 

 Crassatella (Eriphyla) lunulata Conrad, var. parro Dall, Blake Eeport, pt. 1, 



p. 259, 1885; Bull. U. S. Nat. Mus., No. 37, p. 48, 1889. 

 Crassatellites (Crassinella) Guppy and Dall, Pi'oc. V. S. Nat. Mus., xix, p. 



336, 1896. See also, Zittel, Text-book of Palgeontology, i, p. 396, 1900. 



This variety differs from lumdata Conrad in being more elongated 

 in form with the anterior end subtruncated, with a distinct sinuation 

 in the concentric ribs. 



Very common in the shell-sands. 



Family LEPTONID-ffi. 



Lassea Bermudensis Bush. 



Plate LXIII. Figs. 4 and 5. 



Lascea rubra (pars) Dall, Proc. U. S. Nat. Mus., xxi, p. 895, 1899. 

 Lascea Bermudensis Bush, Science, x, No. 243, p. 251, 1899. 



Very common between tides, especially among bunches of mussels, 

 clinging to the byssus. 



Family LUCINID^. 



Lucina nux, sp. nov. 



Plate LVIII. Figs. 12 and 13. 



Shell small, white, higher than long, obliquely ovate in a side-view. 

 Umbos prominent, strongly curved forward. Surface strongly cos- 

 tulate and subcancellate. Posterior dorsal margin descending from 

 the umbos in a broadly rounded curve ; ventral margin distinctly 

 produced and rounded in the middle ; anterior end short, broadly 

 rounded below, subtruncated above. Lunule small, deeply excavated. 



