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727 



TERTIARY FAUNA OF FLORIDA 



Pccten ti-nukostatiis Mighels and Adams, Proc. Bost. Soc. N. Hist., i., p. 49, 1841 ; Bost. 



Journ. Nat. Hist., iv., p. 41, pi. 4, fig. 7, 1842. (Young.) 

 Pectcn /e-?uucos/a/iis\'tn-\\\. Rep. U. S. Fish. Com., 1871-2, pp. 509, 696, 1873. (Adult.) 

 Chlamys {Placopcctcii) Clintonius Verrill {ex parte), Trans. Conn. Acad. Sci., x., pp. 69, 



78, pi. xvii., figs. 1-7; pi. XX., figs. 7, 8, 8rt; pi. xxi., figs. I, \ a, 2, 2 <?, 1897. 

 Pccten iPseudamusiuni) MulleriV&L\\\\, op. cit., p. 78, not of Dall. 

 Pec ten {Pseudamusiwii) striatus Dall, Bull. U. S. Nat. Mus., No. 37, p. 34, No. 40, 1889 



(not of Mviller, fide Verrill), young shell ; Verrill, op. cit., p. 96, in errata, 1897. 

 Pleistocene of St. John, New Brunswick, and Gardiner's Island, New 

 York ; living from Labrador southward, in increasing depths of water, to 

 Cape Hatteras, North Carolina. 



The sculpture of the more northern specimens is less strong than in 

 those from more southern habitat, and for the former Professor Verrill suggests 

 the retention of Mighels's name temiicostatns (originally given to the young 

 shell) in a varietal sense. This is not P. tenidcostatns Hupe, in Gay's Chile, 

 1854. As previously noted, the writer sees no reason why Gmelin's name, 

 given in error as to the true habitat of this species, but universally familiar, 

 should not continue to be used. If, however, an exaggerated purism demands 

 a change the next most appropriate name is that of Solander, given without 

 description in the Portland Catalogue, described in the Banksian MSS., and 

 cited by Humphrey as the Great Compass shell from Newfoundland, with 

 nearly equal valves, remarks which cannot possibly apply to any other species. 

 He not unnaturally places it after the species of Amusium, as H. and A. 

 Adams did in their Genera of Recent Mollusca (ii., p. 55) sixty years later. 



Peoten (Placopecten) virginianus Conrad. 

 Pccten virginianus Conr., Fos. Medial Tert., p. 46, pi. xxi., fig. 10, 1840. 



Miocene of City Point, Virginia; E. Ruffin. 



This is a puzzling shell, of which only the type specimen (a right valve) 

 and one other valve are known. It appears like a young shell of P. Clintonius 

 in all essentials, except that it is more convex and has the byssal ear separated 

 by a broad fasciole and deep notch from the submargin and is provided with 

 a strong and conspicuous ctenolium. The young shells of P. Clintonius of the 

 same size (altitude fifty-eight millimetres) as the type of virginianus have not 

 these characters, as an examination of a large number has shown. A speci- 

 men of the same valve from Coggins Point, Virginia, identified by Conrad as 

 virginianus, seems to me merely a young P. Clintonius with a somewhat deeper 

 notch than usual, but the original type specimen differs more markedly, and 



