FROG. 



the animal with food during the last stage of its trans- 

 formation, that is of the final development of the fore 

 feet, the shortening and change of the intestines, the 

 development of the lungs, and the absorption of the 

 gills ; during which changes, at least in the very last 

 stages of them, the animal can of course neither 

 breathe nor feed in the water. Thus this curious 

 accumulation of nourishment in the tail bears some 

 slight resemblance to that which is provided for the 

 chicken in the egg ; and the moment that the change 

 is completed, the tail is absorbed, the gills are gone, 

 the lungs perfected, and the former tadpole no longer 

 capable of breathing in that element in which it has 

 hitherto lived, leaps out of the water a little frog. 

 The numbers of them that leave the ponds or streams 

 on such occasions are very great, so many as that in 

 particular cases four or five acres of ground have been 

 observed entirely covered with them. Those migra- 

 ting myriads are very frequently thinned by birds, or 

 where serpents abound, by those species which fre- 

 quent moist places, and the banks of rivers. It is proba- 

 ble that those migrations may havegiven rise to the old 

 stories of showers of frogs ; because, whether young or 

 old, frogs are always most active when the air is humid. 

 After their transformation, they are no longer 

 capable of breathing through the medium of water ; 

 and there is a change in the way in which they re- 

 ceive the air. While tadpoles they take in the water 

 and air along with it, by the mouth ; but when they 

 acquire their perfect form, they do not use the mouth 

 in breathing, at least in the process of inspiring or 

 taking in air. They do this through the nostrils ; and 

 after the cavity of the mouth is filled, they elevate the 

 tongue first, to close the nostrils, and then gradually 

 to occupy the cavity, by which means the air is forced 

 into the cells of the lungs, and when it has performed 

 its office, then it is expelled, not by the action of a 

 diaphragm, but by the simple contraction of the ab- 

 dominal muscles. This is a slow process ; but the 

 system does not require very powerful action ; and, 

 when they are sporting in the water, it can be sus- 

 pended for a limited time. 



Frogs in their proper state cannot be considered as 

 inhabitants of the water, though they all resort there 

 more or less, but with different degrees of frequency in 

 the different species. Still they are not found in very 

 dry situations, but in marshy and boggy places, and on 

 the margins of lakes and rivers. They resort to the 

 water for food, which principally consists of aquatic 

 insects, worms, and the very young fry of fishes; they 

 also resort there for the purpose of breeding, and, as 

 it is seen from their gambols in the water, they some- 

 times resort there for mere amusement. 



Frogs, in most of the species at least, are under- 

 stood to arrive at full maturity in about, five years ; 

 and to live for about fifteen or twenty ; but the latter 

 point of course is not very well understood, and from 

 the enemies to which they are exposed, it is probable 

 that but few of them live out the full number of their 

 years, and die of old age. They are susceptible of 

 some attachment ; and there have been instances in 

 which frogs h'ave been rendered so tame as to come 

 when called, and take their food out of the hand of 

 those with whom they had become familiar. We shall 

 now very briefly mention a few of the species. 



THE COMMON FROG. This species requires little 

 description. It is by far the most abundant in the 

 British islands, the most hardy, and the earliest 

 Breeder They are found in many, indeed in most 



countries, but with some variation of size and colour. 

 Their general colour is a dull brownish red, some- 

 thing resembling the tint of a withered leaf; with a 

 black spot on each side of the head, and produced on 

 the sides of the neck. When their several labours of 

 pairing are completed, they quit the parts in which 

 they have deposited their numerous progeny ; and, 

 during the latter part of the spring and the summer, 

 they may be seen hopping about in moist and shady 

 places, especially in moist states of the atmosphere. 

 When the air is very dry, they resort much to the 

 waters, it appearing that they do not feel comfortable 

 if their skins become dry ; while they hide themselves 

 in the tall aquatic plants, they are very quick and 

 dexterous in the capture of water-flies, which they 

 watch with keen eye, and spring upon with certainty. 

 When the temperature sinks below a certain degree 

 in the autumn, they all disappear ; and it is under- 

 stood that they take up their abode in the water, in 

 that element in which they are first awakened into 

 life, and in which they spend the first form of their 

 existence, and undergo their transformations. This, 

 if not absolutely demonstrated* in all cases, as in the 

 nature of things it cannot be, is yet very likely, and 

 very agreeable to the analogy. They neither feed 

 nor breathe during this period of the year ; and as the 

 peculiar texture and secretion of their skins protect 

 them as completely from the action of the water as if 

 they were fishes, they enjoy a much more uniform 

 temperature, and, in cold weather, a warmer one than 

 they would do in holes of the earth. It is not a little 

 curious that animals which cannot be produced or 

 come to their ultimate form but in the water, should 

 resort there in order to bring forward their rggs or 

 spawn ; and yet this is in accordance with the general 

 analogy. The young are, for some time after they 

 come into life, to be fishes in their element, and in the 

 more important purposes of life ; and, perlnips, one 

 might naturally expect that the eggs from which those 

 young are to be produced, should have some resem- 

 blance in the mode of their maturing to the spawn of 

 fishes. It has sometimes been said that at the time 

 when frogs betake themselves to the water for the 

 purpose of hybernating, their mouths grow together, 

 by the one lip forming a complete adhesion to the 

 other. This, however, is not the case, and it is not 

 necessary. The mouth of a frog is not, as we have ob- 

 served, used in the breathing of the animal, but serves 

 merely as a prehensile apparatus in the capture of - 

 he food ; and when not used for that purpose, it closes 

 not only water-tight but air-tight. When the animal 

 ceases to eat, it has no occasion to open the mouth ; 

 and that of course remains closed. It does not appear 

 that they feed in the spring before the time of pair- 

 ing ; and thus they corne out of their hybernating 

 places, with the spawn or eggs fully matured, and 

 ready to be excluded and fecundated, nor do they 

 quit the waters, or eat, or move, until that operation is 

 iilly performed ; and they are absolved from all 

 'amily cares, quit the breeding waters, and leap 

 about until the close of another season shall send 

 hem anew to their hybernating places, to perform the 

 same operations. The common frog is the most pro- 

 lific of all the British species ; and its tadpoles afford 

 an abundant supply of food to various species of birds 

 which breed in trie marshes. 



THE GREEN or ESCULENT FROG (R. esculenta). 

 This is not the only esculent species, for the common 

 frog is equally palatable and wholesome, though it 



