Descriptionary

spinosaurid during the Cretaceous, a large meat eater characterized by a 6-foot (1.8-m) high sail on its back, thought to have been a heat regulator or possibly used for mating displays.

stegosauria during the Jurassic and into the Creta­ceous, a group of ornithischian plant eaters character­ized by a double row of armor plates running down their backs and ending in spikes at the end of the tails. Stegosaurus is the best-known example, also famous for its tiny head and walnut-sized brain.

strata layers of sediment or rock, often marking distinct geological periods (sing., stratum).

Tertiary period the geological period from 1.8 to 65 million years ago, following the extinction of the dinosaurs, within which mammals took center stage.

theropod any bipedal carnivore with hands and claws, ranging from the size of a chicken to 50 feet (15 m) tall, that lived from the Triassic to the end of the Cretaceous. Birds are believed to have evolved from theropods.

thyreophoran living from the Jurassic to the Cre­taceous, any four-legged plant eaters with armored plates, including stegosaurs and ankylosaurs.

titanosaurid a group of very large, four-legged sauropods, characterized by long necks and tails, small heads, and armored backs that lived during the Cretaceous.

T. rex see TYRANNOSAURUS REX.

Triassic period the geological time period from 251 million to 199.6 million years ago, it marked the beginning of the reign of dinosaurs.

triceratops during the late Cretaceous, a four- legged plant eater that grew to be up to 29.5 feet (9 m) long, characterized by its three horns and neck frill.

Tyrannosaurus rex "tyrant lizard," a very large bipedal predator that grew as tall as 43 feet (13 m), had a 5-foot (1.5-m) long skull, and lived in North America during the Cretaceous.

velociraptor a small, swift-footed meat eater that had a slashing, sicklelike claw on each foot and lived during the Cretaceous period. According to the size of its brain case to body size ratio, it was likely among the most intelligent of the dinosaurs.

DOGS

alpha the dominant dog in a pack.

apple head a rounded or domed skull, as in the English toy spaniel.

apron the longer hairs found on the chest of many breeds.

badger-marked having a coat consisting of gray or black markings on white.

bat ear an erect ear that is rounded at the top, as in a bat.

bay a deep bark.

beard the tuft or long hairs under the chin.

belton a coat consisting of blue or orange and white hair.

bitch female dog.

blaze a white or light-colored streak running along the center of the head.

blond having a coat of light yellow or yellowish tan.

bloom the glossiness of the coat.

bobtail a tail cut short; also known as a docked tail.

brindle having a streaked or spotted coat.

brisket part of the chest between and slightly behind the forelegs.

brush a bushy tail.

bullbaiting the long-banned English sport of dogs tormenting bulls.

butterfly nose a nose with two or more different colors.

buttocks the rump.

button ear an ear that folds forward toward the eye, as in a fox terrier.

canine of the dog family, or like a dog.

chops the lower cheeks, especially in a bulldog.

cloddy thickset and low to the ground, as a Scottish terrier.

cobby short-bodied.

crest the ridge of the neck.

crop trimming the ears to make them pointed.

cynology the study of dogs and their history.

cynophobia fear of dogs.

dam mother.

dewclaw one of the short vestigial claws or digits, the remnant of a first toe, now useless.

dewlap the loose fold of skin hanging from the neck of many breeds, such as the bulldog and the blood­hound.

dingo wild dog of the Australian outback.

distemper an infectious disease of puppies and young dogs, caused by a virus.

docking the surgical removal or shortening of the tail.

eyeteeth the two projecting canine teeth in the upper jaw.

fawn having a pale, yellowish brown coat.

feather the fringe of hair along the tail and back of the legs.

feral domesticated but living in the wild.

dogs 9

fiddle front forelegs that are bowlegged.

frill a fringe of hair around the neck.

grizzle having a coat that is gray or streaked with gray.

gun dog any of the sport hunting dogs, such as a setter, pointer, spaniel or retriever.

hackles neck and back hairs that bristle when a dog is angry or fearful.

harlequin having a white coat with black spots of various sizes.

haw the red membrane inside the lower eyelid.

heartworm a worm parasite living in the blood­stream of infected dogs.

heat the female's mating period.

hock the backward-bending joint in the hindleg, corresponding to the ankle in humans.

leather the external part of the ear.