xxvii INFERIOR OOLITE AMMONITES. 



The non-tuberculate, or Eseri group. 



This name may describe the platyleptogyral, angustumbilicate, non-tuber- 

 culate species of the Lillia-Haugia series. It is almost certain that they are 

 polygenetic, the development of different tuberculate species. Somewhat enlarged 

 costae near the inner margin in certain cases point to ancestral tubercles, elon- 

 gated on account of greater involution. 



The description of the species as Haugia ? is merely a matter of convenience. 

 It is probable they belong to more than one genus, some perhaps to Lillia as 

 descendants of Lillia Lilli, some to Phymatoceras, &c. 



12. Haugia? occidentals (Haug). Plate XXVII, figs. 1, 2. 



1890. Haugia occidentalis, This Monogr., PL xxvii, figs. 1, 2, p. 154. 



Remarks. — The specimen figured with the above name differs from the 

 example depicted by Haug ; it is certainly more umbilicate and more coarsely 

 costate. It may deserve separation. 



Locality and Stratum. — Gloucestershire : Little Sodbury (Sands). 



Date of Existence. — Striatuli hemera. 



13. Haugia ? Eseei (Oppel). Plate XXV, figs. 3, 4. 



1890. Haugia Eseri, This Monogr., PL xxv, figs. 3, 4, p. 155. 



Remarks. — The specimen referred to seems to agree particularly with what 

 must be taken as the type, namely, Quenstedt's Ammonites radians compressus in 

 ' Cephalopoden,' pi. vii, fig. 9. 



It was pointed out at p. 156 that the other specimens do not agree so well. 

 It seems desirable to separate them. 



Localities and, Stratum. — Gloucestershire : Coaley Wood ; Cam Down ; North 

 Nibley ; Whitehall Farm, Alderley (in all cases lower portion of the Cephalopod 

 bed). 1 



Date of Existence. — Striatuli hemera. 



1 This and the associated species of the group are generally found just on the top of the lowest 

 limestone band. 



