AMPHIBIANS AND REPTILES. 139 
ovoid as viewed from above, with greatest width at tympani. 
Constriction posteriorly slight. Form rather elongate and 
slender, and depression below greater than that above where 
sides are more or less abrupt, and median surface somewhat 
levelled. Pelvic bones forming an obtuse or rather abrupt angle 
about last 24 in length of head and trunk. Processes rounded 
and not much elevated in profile. Head large, broad, greatly 
depressed both above and below, though former surface more 
or less convex. Snout depressed, its length 134 in its width, and 
when viewed above rather convergent triangularly, tip slightly 
rounded, and sides sloping evenly and convexly back to tympani. 
Eye rather large, elongate, slightly elevated over profile, placed 
nearly midway between shoulder and tip of snout, or about last 
third in length of mouth measured from tip of snout. Mouth 
Wood Frog. Rana sylvatica Le Conte. 
large, gape but slightly undulate in profile. Lips fleshy and 
firm, upper better developed, and closing over lower all around. 
Lower lip firmer than upper, with fleshy process at symphysis 
fitting in above. When viewed below mouth more broadly con- 
vex than edge of upper jaw which protrudes well in front. ‘Teeth 
in upper jaw hidden by lip, uniserial, small, equal, and those in 
front of jaw larger than others. No mandibular teeth, edges 
of jaw hard and firm. Vomerine teeth very small, in 2 small 
widely-separated patches between internal nares, so that space 
between each is about same. ‘Tongue large, rather thick, fleshy, 
elongately ovoid with posterior margin deeply notched medianly, 
leaving a pair of fleshy obtuse appendages directed down throat, 
surface entirely papillose, free more than half its length behind 
