PTARMIGAN PTERODACTYL 61 spots of reddish brown ; only one brood is raised in a season. The rock ptarmigan (L. rupea- tris, Leach) is 14 in. long; the bill is slender, rather compressed at tip ; in summer the feath- ers of the back are black banded with yellow- ish brown and tipped with white; in winter white, with the tail black (the four middle feathers white), and the male with a black bar from the bill through the eyes. It occurs in arctic America, rarely coming further south than lat. 63 K in the interior, but to 58 on Hudson bay, and in the Rocky mountains, ac- cording to Richardson, to 55 ; the same spe- cies is said to occur in the northern parts of the eastern hemisphere ; the eggs are pale red- dish brown, with darker spots, and are If by 1 in. The white-tailed ptarmigan (L. leucu- rus, Swains.) has a slender bill, the plumage in summer blackish brown barred with brownish yellow, and in winter entirely white; it is 13 in. long and 21 in alar extent; it is found in the N. W. portions of America, and to the south along the Rocky mountains to lat. 39. .European Ptarmigan (Lagopus mutus) winter plumage. The common European ptarmigan (L. mu- tus, Leach) is about 15 in. long; the bill is black, short, and robust ; the summer plumage is ashy brown mottled with darker spots and barred with orange yellow and dark brown on the sides of the neck and back, and the tail, with the exception of the two middle feathers, grayish white with a narrow terminal white band. It is fond of lofty and northern re- gions, going as far as Greenland and coming down to the highlands of Scotland ; when pur- sued, like the other species, it is apt to dive under the soft snow; it sometimes does this for protection from the cold, and in damp weather is sometimes imprisoned and destroyed under the frozen surface of the snow; the ruffed grouse has the same habit. A species much resembling this, if not identical with it, occurs in America, in the neighborhood of Baffin bay, and has been described by Audu- bon as L. Americanm. The Scotch ptarmigan or moorcock (L. Scoticus, Steph.) seems pecu- liar to Great Britain, and is abundant in the hilly districts of Scotland ; the general color is chestnut brown, with black spots on the back and undulating black lines below ; the winter plumage is the same. It is highly esteemed as game ; where not much pursued it is not very shy, but its plumage is so like the surrounding dark moss and heaths, that it can hardly be discovered without the aid of a pointer ; it feeds upon heath tops and mountain berries. PTEBICHTHYS. See GANOIDS. PTERODACTYL (pterodactylus, Cuv. ; Gr. nripov, wing, and d<krivlof, finger), a genus of fossil flying reptiles, possessing essentially the characters of saurians, with some only appa- rent relations to bats and birds. They have been divided into three genera according to the number of joints in the wing-bearing finger and the disposition of the teeth ; all are char- acteristic of the secondary epoch, being found principally in the lithographic schists of So- lenhofen, and in the oolite, lias, wealden, and chalk of Europe and the United States. In the genus pterodactylus the jaws had teeth even to the extremity; the skull was elon- gated, with the intermaxillaries large ; nasal opening wide and near the middle of the muz- zle, partly closed in front by a small bone as in the monitors, and with a surrounding circle of small bones and a small opening into the orbit as in birds ; the lower jaw, as in croco- diles, had n@ coronary process, and was articu- lated behind the eyes ; the teeth, 5 to 17 on each side, were conical, slightly arched, com- pressed, inserted in separate cavities, and hol- lowed at the base ; neck of 7 stout vertebrae ; dorsals 13 to 15, and, with the ribs, weak; lumbar 2 or 3, sacral 6, anchylosed together, and caudal 10 to 15; the shoulder blade and coracoid bone separate and weak ; scapu- lar arch and pelvis as in lizards, except that Pterodactyl. the last seems to have had marsupial bones, according to Pictet; the long bones hollow and with air openings, as in birds ; humerus
