294 Mr. W. Warren on new 
division is presented. The enamel-organs of the molars are 
therefore here also in connexion with an epithelial cord, 
which is prolonged laterally on the inside of the dental rudi- 
ments; we have in this case also the representation of the 
origin of teeth of the first dentition before us, although rudi- 
ments of the second dentition are not distinctly formed. ‘The 
epithelial cord terminates further back in a knobbed swelling, 
which is perhaps the earliest rudiment of the fourth molar. 
Although the facts may yet be considerably amplified by 
further investigations, nevertheless I consider that I may 
already maintain that embryology furnishes no support for 
attributing the first two so-called molars of the upper jaw and 
the first three similar teeth of the lower jaw to another den- 
tition than that to which are attributed the rest of the teeth 
which lie in front of them. here are no molars at all, but 
premolars. The dentition of Dédelphys which cuts the gum 
and is permanent therefore belongs (with the exception of 
the last molars, which appear at a late stage of development) 
to the first series, or the milk-dentition. 
XLV.—Descriptions of new Genera and Species of Pyralidee 
contained in the British-Museum Collection. By W. 
W ArrEN, M.A., F.E.S. 
[Continued from p. 179.] 
MICRACTIS, gen. nov. 
A subdivision of Botys. Characterized by the presence of 
a small raised linear dash close to the base immediately 
beneath the mterno-median vein of the tore wing of the male. 
The females are always larger and generally paler than the 
males. 
Type M. nubilalis, Hiib. (Pyralis). 
Micractis sanguinealis, sp. 1. 
Fore wing deep yellow, more or less thickly suffused with 
dull red, the costa throughout deeper; lines themselves red- 
dish; first curved outwardly, preceded by a yellowish space, 
the basal area up to it suffusedly reddish; central space 
between the two lines thickly suffused with red, the two stig- 
mata deeper; second line, slightly serrated, forms a distinet 
