BlXL-p'HOG.- 



-KEPTILES.- 



-ToADS. 



91 



species, received from Cambridgeshire, into a pond 

 near Ins own residence, and tliat tliey soon migrated to 

 anotlier pond, and tliero made tliemselves perfectly at 

 liome. 



THE BULL-FROG {Rana mugiais, ox pipiens) — fig. 25 

 —a North American species, is of a large size, reaching 

 even to the length of twenty-one inches, the body alone 

 measuring seven lengthwise, four or tive across, and 

 weigliing about two pounds. The head of this species 

 is very lai'ge, broader than long. It has a very large 

 moutli, great prominent ej^es, and the vocal sacs are 

 internal. The body is thick and massy, smooth above, 

 and in front it is of a green colour ; dusliy, with only 

 a greenish tinge behind, and marked with irregular 

 blotches of dark-brown. On the sides and belly it is 

 of a yellowish tiut, foding almost to a dusky-white. 

 Bull-frogs are found in almost every marsh and pond 

 of North America, and in general are solitary in their 

 habits, only collecting together in the breeding season, 

 at which time hundreds may be seen in one small pond, 

 and then, says Mr. Ilolbrook, " the croak uttered by 

 the males is so louil as to resemble the distant roaring 

 of a bull, and can be heard on still evenings at the dis- 

 tance of half a mile. During the day they are generally 

 quiet, and only begin their noise at the approach of 

 twilight or in dark cloudy weather." 



There are some species of frogs in Soulli America 

 which are dij-tinguislicd from all others by having the 

 edge of the upper eyelid more or less produced into a 

 point, so as to form a long horn. Azara tells us that 

 in Paraguay the residents do not distinguish frogs from 

 toads, but call all the animals of this order by the 

 general name of toad. At Chaco, he says, "there are 

 some toads which weigh several pounds, and there are 

 otliers very large, which are seen leaping in all the low 

 grounds when there is moisture. They are neither 

 very ugly nor very swollen, and one would say that 

 tliey had ears straight like horns." 



These frogs constitute tlie genus Ci".RATOriiRYS, of 

 which four s]iccies have been described. 



THE HORNED FROG (Cerakiplirys cornntci), which 

 is found in Cayenne and Brazil, is the best known. It 

 is a large species, equal in size to the bull -frog of North 

 America. The head is very depressed in form, and 

 very broad behind, and the mouth is enormously large. 

 The skin is covered nearly all over with tubercles, and 

 is of a cinereous yellow colour, striped w'ith lines of 

 obscure grayish-brown. " It is difficult to find an 

 animal," says Shaw, " of a more singular appearance 

 than the present, not so much from the general shape 

 of the animal as from the extraordinary structure of 

 the upper eyelids, which are so formed as to resemble 

 a pair of shcirt sharp-pointed horns; while the width 

 of the mouth is such as to exceed that of any other 

 siieeies, and even to equal half tlie length of the body 

 itself." The Prince of Wied informs us that it lives in 

 the large, obscure, and moist woods, and particularly 

 in the marshes of Brazil, although it is also met witli 

 in cultivated and even dry places. It leaps well, and 

 towards evening may be heard uttering a monotonous 

 croaking. Its food consists of small mice, birds, and 

 snail frogs, molluscs, and other diminutive animals. 



All our readers are familiar with the plague of frogs 



brought as a punishment upon Pharaoh for refusing 

 liberty to the Hebrews. Though this was a miraculous 

 visitation, ordered by God for a special purpose, it was 

 not contrary to nature. The plague consisted in its 

 unexampled intensity and magnitude, indicated hy the 

 fact that the immense heaps of the carcasses of these 

 animals ultimately corrupted the land ; " and still more," 

 as Dr. Kitto observes, " by the fact that their numbers 

 were such as to force them when alive to forego their 

 natural habits, and, instead of confining themselves to 

 the waters and moist soils, to spread over the country, 

 intruding even into the most frequented and driest 

 places — the most private cliambcrs, the beds, nor even 

 the ovens being exempt from the visitation." The 

 frog was one of the sacred animals of the Egyptians ; 

 and in this instance the oliject of their superstition 

 became the instrument of their punishment. Frogs are 

 still very abundant in the Nile, — 



THE DOTTED FROG {Rana—Pclodyks—punckda), 

 which is of an ash-colour, dotted above with dark spots, 

 being the common species of the country. It is said 

 to change colour when alarmed, and is also found in 

 Europe. 



BuFONiNA, or Toads. 



The Toads are distinguished from the Eanina or Frogs 

 by their having no teeth in the jaw, and by their hav- 

 ing a well-developed ear. In general the tongue is not 

 notched at the tip, but is entire, and longer than in the 

 frogs. Many of them have a smooth skin, but the 

 true toads, species of the genus Biifo, have it covered 

 more or less all over with warty tubercles. The I'.ead 

 varies very much in size and form, being sometimes 

 very small, at others very large ; and the shape of tlie 

 body is equally various. In all of them the processes 

 of the sacral vertebrffi are dilated, and the greater num- 

 ber possess those glands known by the name of paro- 

 tids. The extremities vary much in length, but in 

 many of the species the huider ones are much shorter 

 than in the frogs. The fingers are four in number, 

 all free, and the toes are five, more or less webbed ; 

 while on the plantar surface, in the greater number, 

 there is a tubercle, sometimes greatly developed, 

 which from its position resembles a sixth toe. The 

 males have either one only or two vocal sacs, which 

 are in all of them internal. In the toads as in the 

 frogs we find a number of small glands scattered 

 over the skin, wdiich secrete a viscid fluid. It is said 

 these animals have the power of increasing at will this 

 secretion, and cause it to run out like a dew at all 

 points. This humour was at one time considered to 

 be poisonous, and though this notion is now rejected 

 by naturalists, and the hquid proved to be innocuous, 

 it is yet perhaps possessed of some use as a means of 

 defence. It is somewhat fetid and of an acrid quality, 

 is neither acid nor alkaline, but when evaporated yields 

 a transparent residue, which acts on the tongue like 

 extract of aconite. The use, according to Dr. Davy, 

 may be to defend the reptile against the attacks of 

 carnivorous animals, and may serve, also, he thinks, as 

 an auxiliary to the function of tlie lungs. This poi- 

 sonous reputation of toads, however, is still a common 



