HAUGIA ESERI. 155 



my mind, between H. Eseri and H. occidentalis are the narrower, more quadran- 

 gular whorls with broader ventral area of the latter, accompanied by a larger 

 umbilicus and a deeper inner margin. 



At the same time while the specimen figured in Plate XXV, fig. 7, agrees in 

 the size of its umbilicus with H. occidentalis, in its compressed form and sharpened 

 ventral area it agrees with H. Eseri. After all I cannot consider the differences 

 between the two species as very clearly pronounced (see p. 157). 



H. occidentalis is scarce and I have only met with it at Little Sodbury in the 

 yellow Sands (Striatuhim-heds, Jurense-zone, section xi, Bed 12, p. 165). The 

 specimens are generally fairly preserved. Plate XXVII, fig. 1, illustrates the side 

 view of a good specimen ; fig. 2 is the outline of the aperture. 



Haugia Eseri (Oppel). Plate XXV, figs. 3—7 ; Plate XXVI, figs. 1, 2 ; Plate A, 



fig. 37. 



1846. Ammonites eadians compbessxjs, Quenstedt. Cepbalopoden, pi. vii, fig. 9, 



p. 112. 

 1856. — BsEKi, Oppel. Juraformation, p. 245. 



1858. — EADiANs coMPEEssus, Quenstedt. Jura, pi. xl, fig. 13. 



1862. — EsEEi, Oppel. Palaeont. Mittheilungen, pi. xliv, fig. 3 a, b. 



1874. — EXAEATUS, Dumortier (non Toung and Bird). Depots jurass. 



du Bassin du Ehone, pt. iv, pi. xii, figs. 1, 2, 4 

 {non fig. 3) (pi. xi, fig. 11 ?). 

 1885. Haepoceeas Eseei, Haug. Beitr. Monogr. Harpoceras ; Neues Jahrbuch 



fiir Mineralogie, &c., Beil.-Bd. iii, p. 623. 

 1885. Ammonites eadians compeessus, Quenstedt. Amm. Schwabischen Jura, 



pi. li, figs. 6—8 ; pi. Hi, fig. 4. 



1885. — cf. Ltthensis, Quenstedt. Ibid., pi. liii, fig. 14. 



But NOT — 



1874. Ammonites Eseei, Dumortier. Op. cit., pi. xii, fig. 3 (see later, Grammo- 



ceras, p. 204). 

 1878. Geammoceeas Eseei, Bayle. Explic. carte geol. Franf., pi. Ixxviii, fig. 6 



(see later, Orammoceras, p. 204). 



1886. Haepoceeas Eseei, Vacek. Oolithe Cap San Yigilio ; Abb. k. k. geol. 



Reichsanstalt, Bd. xii, No. 3, pi. ix, fig. 6 

 (Sammatoceras) . 



Discoidal, compressed, hollow-carinate. Whorls broad, ornamented with 

 irregular, often towards the inner margin slightly fascicled, sigmoidal ribs which 

 die away in old age. Ventral area carrying a large hollow-carina. Inner margin 

 distinct, fairly steep, shghtly convex, but in some old specimens showing a decided 



