SKELETON OF FROG. 



farther investigation of these remarkable creatures. The first point which strikes the 

 observer is the shape of the head, and the enormous size of the orbits of the eyes, 

 which are so large, that when the skull is placed flat upon an open book, several words 

 can be read through the orifices. Very little room is left for the brain, and, in con- 

 sequence, the intellectual powers of the Frog are but slender. 



The vertebra are furnished with projections at each side, but the ribs are totally 

 wanting. On account of this deficiency, the process of respiration cannot be maintained 

 as is usual among the better developed beings, but is similar to that which is employed 

 by the tortoises. The needful movements are made not by the sides but by the throat, 

 so that if a quiescent Frog be watched, it appears to be continually gulping something 

 down its throat, as is indeed the case, the material being air, which is thus forced into 

 the beautifully formed lungs. The formation of the pelvis is rather peculiar, and can 

 be comprehended by reference to the illustration, 



The hind-legs are extremely long, and the toes so much lengthened, that in the 

 common English Frog the middle toe occupies about three-fifths of the length of the 

 entire body, and in some species is even more produced. Oving to the peculiar shape 

 of the limbs, the Frog when reposing sits almost upright, and is at once ready for the 



extraordinarily long leaps which 

 it can take when ala'rmed. The 

 usual mode of progression is by a 

 series of jumps, though of short 

 range, but the creature will often 

 crawl after the fashion of the toad 

 the presence of a snake seeming 

 almost always to have the effect 

 of causing the change of action. 

 The skin of the Frog is very 

 porous, and is capable of absorb- 

 ing and exuding water with 

 wonderful rapidity. If a Frog, 

 for example, be kept for some 

 time in a perfectly dry spot, it 

 loses its fine, sleek condition, be- 

 comes thin and apparently ema- 

 ciated, and assumes a very pitiable 

 appearance. But, if it be then 

 placed merely on wet blotting 

 paper, its thirsty skin drinks the 

 needful moisture, and it soon becomes quite plump and fresh. A familiar proof of the 

 extreme porosity of the skin is afforded by the dead Frogs which are often found on 

 the high-road or dry paths * in the middle of summer, and which are dried into a 

 shrivelled, horny mass, which would be shapeless but for the bones of the skeleton 

 around which the skin and muscles contract. 



The whole of these creatures are most tenacious of life, suffering the severest 

 wounds without appearing to be much injured at the time, and bearing the extremes 

 of cold and hunger with singular endurance. Heat, however, is always distasteful to 

 the Frog, and when carried to any extreme becomes fatal. In the hot countries, where 

 Frogs of various species exist, they all unite in the one habit of avoiding the hot 

 beams of the sun by hiding in burrows or crevices during the day, and only emerging 

 from their refuge in the night-time, or during rainy weather. Many species even dive 

 below the muddy soil of pools as soon as the water has nearly disappeared, and there 

 remain moist, torpid, and content until the next rains refill their home with the needful 

 waters. 



Most of the Frogs have a power of changing the color of the skin, which is often 

 found to lose its brightest tints and become dark brown or nearly black, in a very short 

 space of time. Any sudden alarm will often produce this change, the presence of a snake 

 being an almost unfailing means of effecting this object ; and it is known that the color 



SKELETON OF FROQ. 



