375 



parallel with the posterior part of the cardinal border ; beaks small, 

 incurved and placed in advance of the midlength. 



Surface concentrically striated. 



Hinge dentition and muscular impressions unknown. 



Dimensions of the specimen figured: maximum length, 24-6 mm.; 

 greatest height, 11. 



Brennan Creek, V.I., Rev. G. W. Taylor : one specimen and a frag- 

 ment of another, both of which have been kindly presented to the Museum 

 of the Survey. 



Thracia subtruncata, Meek. 



ThraciaC?) subtruncata. Meek. 1857. Trans. Albany Inst., vol. iv, p. 44. 



„ .. Meek. 1876. Bull. Geol. and Geogr. Surv. Terr., vol. ii, no 4, 



p. 363, pi. 2, figs. 4 and 4 a. 

 Whiteaves. 1879. This volume, pt. 2, p. 140, pi. 17, fig. 7. 



Two specimens of this shell were collected at the Sucia Islands by Dr. 

 Newcombe in 1894. 



Pholadomya subelongata. Meek. 



Pholadoiiiya subelongata, Meek. 1857. Trans. Albany Inst., vol. iv, p. 41. 



M Meek. 1876. Bull. Geol. and Geogr. Surv: Terr., vol. ii, no. 



4, p. 362, pi. 2, figs. 1 andl a. 



Pholadomya Royana, Whiteaves. 1879. This volume, pt. 2, p. 140. But probably 

 not P. Royana, d'Orbigny, 1844, which Pictet makes a 

 synonym of P. nodulifera, Munster, in Goldfuss. 



Additional examples of this species have been collected at the Sucia 

 Islands by Dr. Newcombe in 1894, and from the roof of the coal at the 

 Nanaimo mines by Mr. Harvey in 1901. 



Panop^a coxcentrica, Gabb. Var. 



Cfr. Panopcca concentrica, Gabb. 1864. Geol. Surv. Calif., Palseont., vol. i, p. 148, pi. 

 22, fig. 119. 

 Homomya concentrica, Gabb. 1869. Idem, vol. ii, pp. 179 and 236. 



Texada Island, W. Harvey, October, 1901 : two imperfect casts 

 of the interior of both valves, with portions of the test preserved. 

 The larger of these is fully four inches in length and the smaller 

 nearly three and a half. These specimens seem to differ from the 

 Californian types of Panopma (ov Homomya) concentrica in their lon- 

 gitudinally elliptic-subovate rather than subquadrate outline, in their 

 broader, more obtuse and more nearly median umbones, and in their 

 'b% — M. F. 



