- 13: 



and later reported from Gatuii (1). -hat species '-as, however, 

 more concave dorsal nar^-ins anf! v:ider auricles; left vslve with. 



(1). Oahh, ./. M. , Jour. Acad. Kat, Sci., Philadelphia, 2nd ser., 

 vol. 8, p. .'547, 1881, fas Janira soror ). 



slightly hroader and rounded rihs, narrower interspaces an-1 coars- 

 er concentric sculpture v;hich overrides the rihs, the ''.epreasions 

 on the inner marrin ?-/ider and the edges of the elevations more sharp- 

 ly raised; right valve with rihs more rounded and auricles without 

 radials. ^he Gatun P. relic n.us 3ro-;7n and Pilshry (2) has more 

 angular rihs, vrith the concentric lines on the left valve slightly 



(2). Proc. Acad, ilat . Sci., Philadelphia, vol. 64, pp. 510-511, 



pi. 23, fiff. 3, 1912. ( - Pecten sp. (vielleicht n. so.) Toula, 

 1908.) 



vieaker, "but on the right stronger. 



This species is named in memory of Ivlr. Lucas Barrett, the Dir- 

 ector of the early Jamaican Survey, whose premature death was large- 

 ly responsible for the hopeless incoordination of the published 

 results of that organization's investigation. 



Occurrence.- lower Miocene: Bowden beds, "Bowden Jamaica 

 (Ball, 1898). 



