158 INFERIOR OOLITE AMMONITES. 



a nearer ally of his Harp, proximum and Harp. Zitteli, whicli do not belong to the 

 family Hildoceratidce. 



Haugia Eseri is a characteristic species for the Striatulum-beds (Jurense-zone) 

 in Gloucestershire. Its exact horizon is the lowest band of the limestone-capping 

 of the yellow Cotteswold Sands; and I have collected it at Buckholt Wood, 

 Coaley Wood (Bed 8), Cam Down, Stinchcombe, North Nibley (Bed 15), Wotton- 

 under-Bdge and intermediate exposures on the flanks of the Cotteswold Hills. 

 Plate XXV, figs. 3, 4, exhibit the two views of a young specimen of the form a 

 from Coaley Wood ; figs. 5, 6, show two views of form /3 from North Nibley ; fig. 

 7 illustrates the side view of form y with its wide umbilicus and fascicled ribs — in 

 front view this form is if anything more compressed than fig. 6. Plate XXVI, 

 fig. 1, represents a well-preserved fragment of form S from North Nibley ; fig. 2 

 is its aperture. Plate A, fig. 37, shows the suture-line. 



HiLDOCERATiDiE {continued). 

 Genus — Grammoceeas,^ Hyatt, emended.'' 

 (Ti/pe — Geammoceeas steiattjlttm, Sowerly sp.) 



1867. Geammoceeas, Hyatt. Cephalopoda, Bulletin of the Museum of Comp. 



Zool., No. 5, p. 99. 

 1869. Haepoceeas, Waagen. Die Formenreihe des Amm. suhradiatus, Geogn.- 



Pal. Beitrage, Bd. ii, Heft 2, p. 245, pars. 

 1879. Geammoceeas, Bayle. Explic. carte geol. France ; Explanation of PI. 



Ixxviii. 



Discoidal, compressed, mostly evolute. Whorls ornamented with ventrally 

 projected, generally subarcuate^ ribs. Ventral area sometimes broad and sulcate, 

 sometimes narrow and flat or sloping. Carina sometimes hollow, sometimes 

 solid. Termination, in youth with lateral lappets and a ventral projection ; in 

 adult age, plain sigmoidal bend. Suture-line : — Siphonal, superior-lateral, and 

 inferior-lateral lobes short and little ornamented, the superior-lateral but little, if 

 at all, longer than the siphonal lobe ; the auxiliaries practically undeveloped. 



1 Tpafniij, a line. 



2 Of the five species placed by Hyatt in this genus " Qramm. serpentinum" (= Am. falcifer) 

 belongs to Harpoceras, sensu stricto ; while concerning " Oramm. radians " see p. 188. The original 

 definition also requires emendation. 



2 This term is used to denote ribs which are not truly arcuate, first, because of the long ventral 

 projection ; and secondly, because of a slight curve on the lateral area (see PI. A, fig. 45). 



