CRETACEOUS FOSSILS. 235 



THRACIA, Leach. ? T. occidentalis, Meek. 



? Thracia occidentalis, Meek; Trans. Alb. Inst., Vol. 4, p. 43. 

 Chico Group, Nanaimo, Vancouver Island. 



? T. subtruncata, Meek. 



? Thracia subtruncata, Meek ; loc. cit., p. 44. 

 With, the preceding. 



PHOLADOMYA, Sowb. P. subelongata, Meek. 



Pholadomya subelongata, Meek ; Tr. Alb. Inst., Vol 4, p. 42. 

 Chico Group, Nanaimo, Vancouver Island. 



P. Brewer.ii, Gabb. 



Pholadomya Brewerii, Gabb ; Vol. 1, p. 152, pi. 22, fig. 123. 

 Chico Group, Pence's Ranch. 



P. nasuta, Gabb. 



Pholadomya nasuta, Gabb ; Vol. 1, p. 152, pi. 30, fig. 124. 

 Martinez Group, Martinez. 



P. Oregonensis, Gabb. 



Pholadomya Oregonensis, Gabb ; Vol. 2, p. 178, pi. 29, fig. 65. 

 Chico Group, Siskiyou Mountains. 



G0NI0MYA, Agas. G. borealis, Meek. 



Pholadomya (Goniomya) borealis, Meek ; Tr. Alb. Inst., Vol. 4, p. 41. 

 Chico Group, Nanaimo, Vancouver Island. 



PLEUROMYA, Agas. P. papyracea, Gabb. 



Pleuromya papyracea, Gabb ; Vol. 2, p. 178, pi. 29, fig. 66. 

 Shasta Group, Cottonwood Creek. 



ARCOMYA, Agas. A. tjndulata, Gabb. 



Arcomya undulata, Gabb; Vol. 2, p. 179, pi. 29, fig. 67. 

 Chico or Shasta Group, Indian Creek, Butte County. 



