xlvi INFERIOR OOLITE AMMONITES. 



curves points out that small differences in mode of growth and ornamentation 

 cannot be disregarded, and that a separation on the present lines is imperative. 



Remarks. — The specimen depicted in PL XIII, figs. 1, 2, is a fine shell. It 

 shows distinctly the amount of the overlap of what is called the dorsal fold of 

 the mantle — on the commencement of the ultimate whorl ; but this has not been 

 brought out in the drawing. 



Locality and Stratum. — Haresfield Hill, with the preceding species. 



Date of Existence. — Opaliniformis hemera. 



Note. — What has been hitherto called opalini hemera — the date of the 

 deposition of beds with a species supposed to be opalinus — may now be known, to 

 avoid undue change, by the term opaliniformis hemera. 



5. Cyi'holioceras aff. opaliniforme. 



1884. Hakpoceuas opalinum, Wright, Monogr. Lias Ainm. Pal. Soc, pi. lxxx, 



figs. 6— S. 



Note. — Wright's figures appear to depict a distinctly stouter specimen than 

 my type of opaliniforme. Except for umbilication it is a homceomorph of 

 Lioceras grave. 



Locality and Stratum. — " Haresfield Hill " (Wright) [and from the same bed 

 as the other species]. 



C. Cypholioceras renovatujm, S. Buchnan. Plate XIV, figs. 7 — 9 ; Suppl., 



Plate X, fig. 5. 



1888. Lioceeas sp. ?, This Monogr., PI. xiv, figs. 7—9. 



Description. — Platyleptogyral, excentri-angustumbilicate, flexistriate changing 

 to flexicostate. 



Note. — The central part of the umbilicus is very small, and concave. Then 

 excentricity commences, and soon afterwards there is the change from striae 

 to costse. 



Distinction. — Quite separable from the other species of the genus by umbili- 

 cation and ornament. It is a "renovate" species, somewhat comparable to 

 Lioceras comptum, so far as change of ornament is concerned, otherwise there is 

 no likeness. 



It is very similar to Lioceras sp., No. 16, and exact' comparison is not easy. 

 In this case, however, there seems to be, in addition to the longer peripheral 

 projection to the radius, a less distinct carina. 



Locality and Stratum. — Haresfield Hill, with the preceding species. 



Date of Existence. — Opaliniformis hemera. 



