102 A. Smith Woodward — Acrodus Pod-Liassic. 



and these seem to be most nearly paralleled in the smaller species, 

 A. minimus, which occurs so abundantly in the Ehaetic formation. 



From those of A. leiopleurus, the present teeth are readily dis- 

 tinguished by the flatness of the grinding surface, and the rounded 

 character of the ornamental rugae. And there can be no doubt of 

 their distinctness from A. falcifer of the Solenhofen Lithographic 

 Stone, for Wagner's specimen of the last-named species has every 

 appearance of being adult, and yet has teeth of much smaller size ; 

 while there is good evidence, also, that in the present Bathonian form 

 the symphysial teeth were rounded and not acuminate. 



Formation and Locality. — Great Oolite — Stonesfield, Minchin- 

 hampton ; Forest Marble — Atford near Bath. 



A. LEioPLEUEus, Agassiz (" Eech. Poiss. Foss." vol. iii. p. 145, 

 pi. 22, fig. 5). 



This species is founded upon a single tooth in the Bristol Museum, 

 supposed to have been derived from the Great Oolite ; and its chief 

 characteristics are the height of the crown and the angularity of the 

 ornamental wrinkles upon its surface. A beautifully perfect tooth 

 from the Great Oolite of Minchinhampton, preserved in the Byne 

 Collection, appears to be referable to the same form, only differing 

 in the extension of the ornament over the lateral prominences ; and 

 it seems not improbable that this slight divergence depends merely 

 upon the abraded character of the original type specimen. 



A. ELEGANS, Sauvage (Mem. Acad. Boulogne-sur-Mer, vol. ii. 

 ]867, p. 51, pi. iii. %. 9). 



From the Great Oolite of Caen, Normandy ; appears to be wrongly 

 placed in the genus under consideration. The few specimens avail- 

 able for study leave little doubt that they belong to a species of 

 Strophodus. It ought, however, to be added, that satisfactory evidence 

 of the complete dentition of the latter genus has only been obtained 

 since Dr. Sauvage's original description. 



A. HiRUDO, Agassiz (" Rech. Poiss. Foss." vol. iii. p. 148, pi. 22, 



fig. 27). 



The type specimen of this form is said to be preserved in Dr. 

 Mantell's collection, but was not received among the fossils sent to 

 the British Museum. A very characteristic tooth, however, from the 

 Wealden of Telham Hill, near Battle, has recently been presented by 

 John Edward Lee, Esq., F.G.S., and this (No. P. 4991) seems worthy 

 of a passing note. The summit has been considerably abraded, so 

 that the longitudinal wrinkle of the enamelled surface is represented 

 rather as a faint groove ; but numerous very fine corrugations are 

 directed transversely outwards on either side, exactly as remarked in 

 Agassiz' original description. The coronal surface has a remarkably 

 unusual contour, being distinctly concave in the median portion, and 

 rising into a slightly tumid prominence at either extremity. 



A. LEVIS, sp. nov. 



None of the Cretaceous teeth hitherto described under the name 



