192 INFERIOR OOLITE AMMONITES. 



Grammoceras aalense, Zeiten. Plate XXXI, figs. 15, 16 ; Plate XXXII, figs. 1 — 10. 



1832. Ammonites Aalensis, Zieten. Verstein. Wiirtt., pi. xxviii, fig. 3 



1843. — CANDIDUS, d'Orhigny. Ceph. Jurass., pi. Ixiii. 



1843. — AALENSIS, d^Orhigny. Idem, Texte, p. 238. 



1846. — Aalensis, Quenstedt. Cephalopoden, pi. vii, fig 7. 



1856o — — Oppel. JuraformatioD, p. 248. 



1867. Gkammoceras aalense, Hyatt. Ceph. Mus. Comp. Zool., p. 100. 



1874. Ammonites Aalensis, Dumortier. Etudes paleont. Bassin du Rhone, iv, 



pi. 1, figs. 1 — 3. 



1879. LuuwiGiA Aalensis, Bayle. Expl. carte geol. France. PI. lxxix,figs. 1 — 3. 



1881. Haupoceeas dispansum, S. Buchman (uon Lycett). Inf. Ool. Amm. ; Quart. 



Journ. Geol. Soc, p. 605 (pars). 



1885. — Aalense, Haug. Beitrage Monogr. Harpoceras ; Neues 



Jahrbuch fur Mineralogie, &c., iii, 

 Beil.-Bd., p. 667. 



1885. Ammonites cf Aalensis, Quenstedt. Amm. Schwabischen Jura, pi. liv, 



figs. 51, 52, only. 



But not : — 



1883. Haupoceeas Aalense, Wright. Lias Amm. ; Pal. Soc, pi. Ixxv, figs. 8 



{Lioc. opalinum),9 {Oramm. costulatum) , 

 10 {Gramm. mactra). 



1884. — — — Ibid., pi. Ixxx, figs. 1 — 3 ; pi. Ixxxii, figs. 



1, 2 {Dumort. radiosa), 3, 4 (^Dum. 

 Levesquei) . 



Discoidal, compressed, carinate. Whorls broad, flattened, ornamented with 

 ventrally-projected subarcuate radii, which are sometimes, on the inner whorls, 

 united in twos towards the inner margin. Ventral area not defined, acute, carrying 

 a small, barely distinct, solid carina. Inner margin well defined, smooth, nearly 

 upright. Inclusion about one-half. Umbilicus open, scored with irregular, some- 

 times united ribs. Termination, in youth with a short lateral lappet and a small 

 ventral process ; in adult probably subsigmoidal, without a projected lateral lappet.^ 

 The suture-line simple, with only one auxiliary lobe (PI. XXXII, fig. 6). 



Gramm. aalense is a somewhat variable species ; but the chief direction of its 

 efforts seems to have been towards a smooth whorl, and greater compression. The 

 species is undoubtedly descended from Gramm. Jiuitans ; and the well-ribbed 

 form (a) differs from that species only in being more compressed, and having some- 

 what more slender ribs. 



PI. XXXII, figs. 1, 2 represents the adult of this form, which may be con- 

 sidered typical ; and fig. 3, which agrees best in size and ornaments with Zieten's 

 figure, is probably the young of the same. 



1 The shape of the termination is shown by the specimen figured PI. XXXII, fig. 1, but the 

 edges of the mouth are ragged. 



