cxxxviii INFERIOR OOLITE AMMONITES. 



Distinction. — From P. aalensis, finer ornament. 

 Date of Existence. — Aalensis hemera. 



3. Pleydellia leura (8. Buckman). Plate XXXIII, figs. 8 — 10 (type) ; figs. 5 — 7; 



Suppl., Figs. 115, 116, pp. clxv, clxvii. 



1890. Grammoceras leu rum, This Monogr., PL xxxiii, figs. 5 — 10, p. 195. 

 1902. Pleydellia leura, Emend. Amm. Norn., p. 4. 



Remarks. — The two specimens figured as Grammoceras leurum in PL XXXIII 

 differ in details of suture line : the larger one is brevilatilobate, the smaller one is 

 sublongi-subangustilobate. On the test of the smaller example, however, are 

 certain marks, and there are also some slight irregular markings around the peri- 

 phery ; so perhaps this specimen is not quite normal, owing to some injury. 



Date of Existence. — Aalensis hemera. 



4. Pleydellia comata, S. Buckman. Suppl., Plate X, figs. 11 — 13. 



Description. — Obscuriparvicostate to striate ; angustumbilicate. 

 Distinction. — From P. leura, smaller, less distinct ornament. 

 Locality and Stratum. — Dorset : Burton Bradstock, high up in Yeovil Sands. 

 Date of Existence. — Aalensis hemera. 



The following species belong to several series which cannot at present be more 

 definitely separated. They are placed here for convenience. 



5. Pleydellia? subcompta ? (Bra mo). Plate XXX, figs. 13, 14; Suppl., Fig. 117, 



p. clxvii. 



1890. Grammoceras subcomptum, This Monogr., PI. xxx, figs. 13, 14; p. 198. 

 1902. Pleydellia subcompta, Emend. Amm. Nom., p. 4. 



Remarks. — The side view is drawn too flat, and the peripheral view not stout 

 enough. The identification with Branco's species is very doubtful. 



6. Pleydellia? sp. A., Plate XXX, figs. 11, 12; Suppl., Fig. 118, p. clxvii. 



1890. Grammoceras subcomptum, This Monogr., PL xxx, figs. 11, 12 ; p. 198. 

 Remarks. — A much compressed shell, much thinner than the last. 



