2A4 ON THE GLOSSOPHAGINA. 
for grinding. In the upper jaw, with the exception of an interval on either side of the 
canine, all the teeth are contiguous.* In the lower jaw there is no interval on either 
side of the canine, for the lateral incisor and the first premolar are in contact with it. 
The upper incisors are arranged in a small are, which is smaller than the space between 
the canines. 
The central incisor is hatchet-shaped, the outer margin concave. The lateral incisor 
is smaller than central, with inner border twice the length of the outer. The canine is 
coneave on the palatal surface. The premolars are triangular subequal, yet the heel of 
the second tooth is twice the size of the first. The cingules are scarcely discernible. 
The first molar is subtriangular with W-shaped crown reduced, the fiuting on the para- 
conid, rudimental ; the metacone is united to protocone by a ridge. The second molar is 
subquadrate, W-pattern scarcely reduced; the fluting on the paracone marked; the 
ridge from the metacone not reaching the protocone, but a distinet though narrow valley 
intervening. The third molar is one-half the size of the second, the second V being 
rudimental. The longitudinal axis of both second and third molar is oblique to axis of 
the alyeolar processes. The third molar slightly oyerlaps the second at the buccal 
border. 
The lower incisors are proyided with flat smooth edges to the crowns and are 
adapted to crushing rather than to cutting food. The canine is directed slightly back- 
ward and is provided with a small heel. The premolars are triangular, equal, the bases 
increasing in thickness from before backward. The molars exhibit marked commissural 
extension in advance of protoconid and paraconid. The hypoconid is cuspidate and as 
high as metaconid ; all the teeth are much alike, but become progressively smaller and 
narrower from the first to the third, while the extension in front of the paraconid and 
protoconid become Jess and less marked. The third tooth is not more than two-thirds 
the length of the first. 
In a skull of an embryo which measured 8mm. long, the lower jaw projected well in 
front of the upper and. bore the deciduous canines. The shapes of the incisors and pre- 
molars could be discerned, while the upper jaw was edentulous. 
Tn an adult which retained the right upper lateral incisor only and the molars were 
much worn, the only teeth in the upper jaw that were in contact were the second and 
third molars. In the lower jaw the third molar was separated from the tooth both the 
first and third. The lower incisors were much worn and placed slightly in adyance of 
the lateral teeth. I am inclined to believe these are variations due to advanced age. 
* The upper incisors as represented by Leche (Studier ofver Mjolkdentionen och Tindernas Homologier hos Chiroptera, 
1876, Tab. If, VIL) do not touch. 
