548 



FROG. 



fleshy, adhering to the sides of the under jaw, but 

 capable of being elevated against the palate, so as 

 completely to close the communication with the nos- 

 trils. It will be perceived that this structure of mouth 

 is a simple swallowing one ; and that a frog can 

 neither bite nor masticate. This points immediately 

 to the kind of food on which it must subsist, namely, 

 food which it can take into the stomach without any 

 preparation ; and in the taking of this food, frogs are 

 of considerable service to man on the land, and not 

 altogether useless in the water. The different species 

 of slugs, which are so very destructive in gardens, 

 and to many culinary and other useful plants, form 

 one principal article of the food of frogs ; and, there- 

 fore, frogs are deserving of much encouragement, in 

 consequence of the value of their labours ; and, while 

 their labours are thus valuable, they themselves harm 

 nothing. They do not burrow in the earth, neither 

 do they eat any vegetable substance so far as is 

 known ; and, therefore, while they tend to preserve 

 vegetation in the moist places of the garden, and 

 indeed ia all places of it on those damp and dewy 

 nights in which slugs are so mischievous, they are 

 always worth protecting ; and not only so, but it is 

 worth while to keep a little pond for their aquatic 

 amusements, nor, perhaps, is it altogether amiss to 

 have a bit of stagnant water in some waste place, in 

 which they may breed ; for, though the nuptial songs 

 of the frogs are not the most melodious in the world, 

 there is an association of cheerfulness with their 

 croaking their song, such as it is, is a song of hope ; 

 it tells us that the season of growth and beauty is 

 coming, and in the case of the common frog, it tells 

 this very early in the season. 



There is another reason why some attention should 

 be paid to frogs, and that is their value as an article 

 of food. Both the common frog and the green frog, 

 which is specially called the esculent one, are fit for 

 this purpose ; and, though there is a prejudice against 

 them in Britain, it is an exceedingly ill-grounded and 

 foolish one. It is even worse than this, because it is 

 a remnant of that ancient political animosity which 

 existed so long between England and France ; and 

 which, unfortunately for both nations, kept the nearest 

 and most powerful neighbours, whose best interest it 

 was to be at peace, as they could mutually serve each 

 other at the least expense, in a state of constant war, 

 or, at all events, in a panic of mind always prepared 

 for battle. This part of the prejudice is nearly ex- 

 ploded ; and it would be just as well to explode the 

 other part ; and as we do not now hate Frenchmen, 

 so neither should we loathe frogs. The hind legs 

 and thighs of the frogs are the only parts which are 

 eaten ; because they are the only parts which contain 

 much muscle ; and this muscle is firm, white, well- 

 flavoured, and exceedingly nourishing. This is, in fact, 

 the case with the muscle of all esculent reptiles, and 

 it arises from the quantity of gelatine, of a very pure 

 description, which exists in all the parts of them. 



Frogs have no trace of ribs in their skeletons ; the 

 sternum is formed at the under part of a cartilaginous 

 appendage, and it terminates in a disc under the 

 larynx which is united to the clavicles, while a disc 

 at the other extremity, immediately in front of the 

 belly, is attached to the abdominal muscles only. 

 The bones of the skull are of a prismatic shape, flat- 

 tened above, and enlarged posteriorly ; all the bones 

 of the skull and face are soldered into one piece. 



e head is articulated by two condyles to the ster- 



num, so that the head has very little motion on tne 

 neck. The sacrum is long, pointed, and compressed, 

 but there is no os coccygis, nor any production bear- 

 ing the least resemblance to a tail. This is the more 

 curious, because the young of all the species of frogs 

 have tails as their only organs of motion ; and one 

 species the Surinam frog has this organ so large in 

 proportion to that part which is afterwards to be de- 

 veloped into the perfect frog, that the young was long 

 considered as a kind of fish. 



There is something in the muscles of a frog worthy 

 of more attention than it has hitherto received. The 

 principle of animal life in frogs appears to be in a 

 very extraordinary manner obedient to external cir- 

 cumstances ; to be much less concentrated upon a 

 peculiar organisation than that of many other verte- 

 brated animals ; and to make at least an approach to 

 some of the modifications of action, which can be 

 made to take place without the presence of any tiling 

 which we can call either animal life or organisation. 

 It was by operating on the muscles of a dead frog, 

 and finding that they were excited to action by pecu- 

 liar applications of different metals, that galvanism, 

 or humid electricity electricity by chemical de- 

 composition, was at first discovered ; and though the 

 muscles of other animals, even the warm-blooded ones, 

 including those of man among the rest, can be excited 

 by the same kind of action, yet they cannot be so 

 strongly excited by so small a degree of it in propor- 

 tion ; and they do not preserve the capacity of being 

 excited for solonga period after the death of the animal. 



There is another circumstance in the life of animals 

 of this family, which is also worthy of attending to, 

 and that is the time that they will live, and the mus- 

 cular parts indeed, almost any remaining parts 

 perform their functions after other parts are taken 

 away. Almost any animal can admit of having one 

 or more of the extremities removed, and still continue 

 to live ; but any serious abridgment of the internal 

 parts is in most animals attended by a total suspen- 

 sion of all motion in the remaining muscles. But a 

 frog will not only live but leap about after the head 

 and the greater part of the viscera are removed ; and a 

 male frog will continue the operation of fecundating 

 the eggs for a good many hours after his head is cut 

 off. This, and also the circumstance previously men- 

 tioned, tend to show that there is some connection 

 between electric action and the action of life in the 

 bodies of animals ; and when we bear in mind that the 

 life of animals is always the more easily destroyed 

 the more that it is concentrated upon one perfectly 

 organised system, and the more vigorously that that 

 system requires to act in order to maintain itself in 

 the living state ; then, though we cannot see where to 

 draw it, there is a line of distinction somewhere to be 

 drawn, between organisation as a congeries of mate- 

 rial substances, and action as giving what we call life 

 to those substances ; and that as when we chemically 

 analyse the bodies of animals, we find them made up 

 of the common elements of matter ; so when we pro- 

 ceed to the virtual analysis of this connection between 

 the organised body, and the action of life in that body, 

 we feel, though we know not well how to express the 

 feeling, that as the substance of the body is a particu- 

 lar modification of that substance which we can with 

 perfect propriety generalise under the name of matter, 

 so the life of the body the merely animal life is 

 also a particular modification of that which we can 

 generalise under the name of action in matter. 



