MA.CKIE — ON A NEW SPECIES OF HTBODTJS. 
245 
straight and conical as that primitive type itself. Perhaps, however, 
this is but a fanciful idea, and time will not now allow us to work it 
out. 
The species given by Professor Morris are — 
From the Chalk (error, should be Wealden, s. j. m.) — H. sulcatus ; species, chalk, 
Northfleet (Wetherell Coll.), Norfolk (Rose Coll.) ; Lower Greensand (? Wealden, s. j. m.), 
— H. hasanus I Wealden, — jff. subcarinaius ; Portland, — H. strictus ; Kimnieridge 
Clay,— H.^acutus, H. leptodus ; Common to both Great Oolite and Wealden, — H. dubius, 
H. dorsalis (Hastings), H. marginalis, H. striatuiiis ; Great Oolite, — H. apicalis^ H. 
grossoconus, H. Lawsoni, H. obtusus, H. pohjprion, H. undulatus ; Inferior Oolite, — 
H. crassus ; Lias, — H. carinatus, U. crasuforiuis, H. curtus, H. Delabechei, H. 
ensatus, H. formosus, H. medius, H. pyramidalis, H. raricostatus, U. reticulatus ; 
Trias? (Lias Bone bed, s. j. m.), — H. lavinoculus, H. plicatilis, H. minor ; from the 
Keuper of Worcestershire, — H. keiiperianus. 
The following are the specimens of Hybodus in the British 
Museum : — Back tooth of Hyhodus polyprion, Agassiz, from AVealden 
of Tilgnte Forest (Mantell Coll.) ; back tooth of Hyhodus (? sp.) 
from Wealdeu of Sussex (Dixon Coll.) ; several front teeth of Hy- 
hodus (? sp.) from Wealden, Tilgate Forest (Mantell Coll.) ; front 
teeth of Hyhodus yrossiconus, Agassiz ; Wealden, Tilgate Forest 
(Dixon Coll.) ; others of same species, no locality given, but name of 
"P. Doran" attached to label; two others of same species from 
Forest Marble of Atford, collected by Mr. Wood ; some from the 
Forest Marble of Stanton, presented by W. Cunnington, Esq. ; one 
from the Forest Marble of Malmesbury, collected by Mr. Buy; one 
seemingly of the same species from the Great Oolite of Stonesfield ; 
several from the Forest Marble of Wiltshire (W. Cunnington, Esq.) ; 
two from Stonesfield Slate of Oxfordshire (Mantell Coll.), several from 
the Stonesfield Slate of Eyeford, collected by Mr. Binfield. Back 
teeth of Hyhodus polyprion, from the Stonesfield Slate of Eyeford 
(Mr. Binfield) ; one from Great Oolite of Stonesfield, presented by 
S. P. Pratt, Esq. ; one also apparently of the same species from the 
Great Oolite of the same locality ; two from the Stonesfield Slate of 
Oxfordshire (Mantell Coll.) ; three anterior side-(?) teeth, seemingly of 
this species, from the same formation and district ; a posterior (?) side- 
tooth from Great Oolite of Stonesfield ; four largish teeth of a Hy- 
bodus, apparently H. polyprion, from the Great Oolite of Malton 
(Bean Collection). Two back teeth of Hyhodus reticulatus, Agassiz, 
from the Lias of Lyme Regis ; six of Hyhodus pyramidalis, Agassiz, 
Lias, Lyme Eegis ; a very fine mass of jaw, and numerous teeth of 
Hyhodus reticulatus, Lias, Lyme Regis; slab with numerous large 
and fine teeth of a species of Hybodus, Lias, Lyme Regis; very 
fine congeries of back teeth of a Hyhodus, seemingly the same 
