508 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 25, 
in Plate XXXIV. fig. 1. During the past year I have examined 
the collections of Mr. Whincopp, of Woodbridge, of the Rev. H. 
Canham, of the Mayor of Ipswich, of the Ipswich Museum, of Mr. 
MacLean of Yarmouth, of Mr. Roper of Lowestoft, of the British 
Museum, and others less extensive, with the view of obtaining further 
evidence as to this new British Mastodon. The result has been that 
in Mr. Whincopp’s collection I observed two fragments consisting of 
two constituent ridges of a mastodont molar quite distinct from MW. ar- 
vernensis. In the collection of Mr. Canham I found three fragments, 
two of which are here figured (Pl. XX XIV. figs. 3, 4), one of which is 
very similar to those belonging to Mr. Whincopp; in the British Mu- 
seum three similar fragments were detected with the aid of Mr. Davis, 
one (no. 27850) consisting of 23 ridges, two others (28994 and 28253) 
being terminal ridges with a talon like that in the figure. These eight 
fragments do not furnish evidence of the Tetralophodont or Trilopho- 
dont character of the teeth from which they came; but they agree 
in important characters with the thoroughly typical three-ridged 
molar belonging to Mr. Baker. In the collection of Mr. Roper, of 
Lowestoft, I observed a much worn Mastodon molar presenting but 
three widely set ridges; and a similar specimen was purchased by 
Mr. Charlesworth at Felixstow in the summer. 
The perfect molar* of Mr. Baker, and the fragments since observed, 
belong to that form of Mastodon tooth which is furthest removed 
from that of M. arvernensis, the only Mastodon hitherto known in 
the Suffolk bone-bed. In place of the complicated interrupted 
valleys of that species, we have wide and clear valleys with simple 
primary transverse ridges, such as Mastodon ohioticus presents. 
Mastodon Borsoni, which presents free valleys and a three-ridged 
structure of the penultimate and anterior molars, is found in asso- 
elation with Mastodon arvernensis in Central France ; hence it is not 
improbable, prima facie, that the new Crag Mastodon belongs to 
that species. A close comparison of specimens is, however, dif- 
ficult, for we have no specimens of molars of M. Borsoni in the public 
collections of this country, and moreover the material at present 
obtained from the Crag is scanty. It is unfortunate (though of ex- 
ceeding interest from another point of view) that the valleys in Mr. 
Baker’s otherwise perfect specimen are occupied by a sandstone 
matrix, that of the Diestien ‘“ box-stones,’’ which cannot be re- 
moved ; hence the character of the transverse valleys in this speci- 
men is not quite clear. Mr. Canham’s and other specimens, how- 
ever, show perfectly simple valleys, agreeing with those of Borsont, 
with one exception, the fragment drawn in Pl. XXXIV. fig. 4. 
If not M. Borsoni, the only other species which the new Suffolk 
* M. Lartet, of Paris, has expressed to me doubtsas to the complete character 
of the specimen, after inspecting a cast of the upper surface, and would look 
upon it as a fragment of an ultimate molar of Zetralophodon longirosiris. I 
must, therefore, insist especially on the fact that this is a perfect enamel crown, 
of three ridges; and my friend Mr. George Busk, F.R.S., than whose no better 
opinion can be found, authorizes me to state that this is his opinion also, after 
eareful examination of the specimen. 
