TRIGONIA. 81 



Types. — I have not found the type. The specimens figured by Lycett are in the 

 Museum of Practical Geology (figs. 1 — 3), and in Mr. Vicary's collection (fig. 4). 

 Distribution. — Blackdown Greensand (Zone x). 



Section 5. — Scabrj];. 

 Trigonia Etheridgei, Lycett, 1875. 



1875. Lycett, p. 127, pi. xxvii, figs. 1 — 3. 



Types. — In the Museum of Practical Geology. 

 Distribution. — Perna-hed of Atherfield. 



Trigonia caudata, Agassiz, 1840. 



Additional Synonymy. 



? 1862. Trigonia aliformis, F. J. Pidet and W. Roux. Moll. Foss. Gres verts de 



Geneve, pi. xxxv, fig. 1 (not fig. 2), p. 450. 

 1866. — CAUDATA, F. J. Pidet and G. Camjpiche. Foss. Terr. Cret. Ste. 



Croix (Mater. Pal. Suisse, ser. 4), p. 374. 

 1869. — — P. de Loriol and V. GilUeron. Mon. Urgonien Infer. 



du Lauderon (Mem. Soc. helvet. Sci. nat., 

 vol. xxiii), p. 15. 

 1875. — — Lycett, p. I2it, pi. xxvi, figs. 5—7. 



1895. — — G. Maas. Zeitschr. der deutsch. geol. Gesellsch., vol. 



xlvii, p. 264. 

 1900. — — ^1. Wollcmanu. Die Biv. u. Gastrop. d. deutsch. u. 



hoUiiud. Neoc. (Abhaudl. d. k. preussisch. geol. 

 Land., N. F., pt. 31), p. 89. 



Types. — From the Neocomian of Neuchatel. The specimens figured by Lycett 

 are in the Museum of Practical Geology. 



Distribution. — Crackers of Atherfield. Recorded by Topley (1875) from several 

 localities in the Weald — I have not seen the specimens ; it is probable that some of 

 them are examples of T. vectiana. 



11 



