Amplexus:  In amphibians, the sexual clasp of a female by the male.

Carapace:  In turtles, the upper portion of the shell.

Cirrus:  In some salamanders, the pair of slender appendages protruding from the front of the upper lip.

Cloaca:  The common opening for reproduction and waste excretion.

Costal Groove:  In salamanders, the vertical depressions along the side of the body.

Cranial Crest:  In toads, raised ridges on the head.  May be interorbital (between the eyes) or postorbital (behind the eyes). 

Cusp:  A toothlike projection in turtles.

Diploid:  Having chromosomes in homologous pairs.

Dorsal:  The upper surface.

Dorsolateral Fold:  In frogs of the genus Rana, one of the ridges extending from the eye along the dorsal surface of the body.

Fossorial:  Adapted for digging or burrowing.

Frontal:  In snakes and lizards, a large central plate on top of the head between the eyes.

Gill Slit:  One of the paired openings from the pharynx to the outside, located just in front of the forelimbs.

Hemipenis:  In lizards and snakes, one of the paired copulatory organs. 

Labial:  In some reptiles, one of the scales bordering the lip.

Marginals: In turtles, the scutes on the outer edge of the carapace.

Melanistic:  More than normal amount of the black pigment, melanin.

Mental Gland:  In salamanders, a gland beneath the chin in some males.  Secretes a subtance that is a sexual stimulant to females.

Nasolabial Groove:  In salamanders in the family Plethodontidae, a groove extending from the naris (nasal opening) to the upper lip. 

Paratoid Gland:  In toads, a glandular swelling behind each eye.

Phalanges:  The finger bones.

Pheromone:  A substance secreted by an individual that influences a physiological or behavioral response from another individual of the same species.

Pit:  In pit vipers, a deep cavity between the eye and nasal opening which serves as an infrared detector in locating warm-blooded prey.

Plastron:  In turtles, the lower portion of the shell.

Scute:  In reptiles, a modified (usually enlarged) scale.

Spiracle:  In tadpoles, an opening to the outside from the gill chamber.

Tetraploid:  Having chromosomes in two homologous pairs.

Venter:  The belly.

Ventral:  Pertaining to the lower surface.

Vocal Sac:  In male frogs and toads, an inflatable pouch in the throat or one of the inflatable pouches in the sides of the neck.