1920 



TYPE AMMONITES— III 



CLXVI 



Fig. i 



Via. 2 



x 1.5 



Ammonites retentus, Simpson 1855, Holotype 



P. 84 ; 1884, pp. 120, 121 ; R[obin] H[oodsl Bay ; Lower Lias ; 



Mus. Geol. Surv. Engl. (Clarkson Coll.), No. 26401 ; 



S. 23, 54, 21, 10. Cf. CXLIV 



RETENTICERAS RETENTUM, Simpson sp. 

 Deiran, simpsoni ; Genotype 



