I70 OVIPAROUS QJJADRUPEDS. 



though no bone is yet formed, the fhape of the foot is difcoverable. The 

 front legs remain hidden by the covering fkin. The mouth of the tad- 

 pole is under the head ; fo that, like the (hark, it muft turn on its back to 

 catch any thing above it: this motion they execute with almoft imper- 

 ceptible rapidity. The twenty-firft day the egg- opens a little on one 

 lide, and the tail peeps out, becoming more and more diftinft every day. 

 The thirty-ninth day the little animal begins its motion, moving at in- 

 tervals its tail ; and the liquor in which it is circumfufed perceptibly 

 ferves it for nourifhment. in two days more, fome fall to the bottom; 

 while others remain fwimming in the fluid around them, increafing in 

 vivacity and motion. Thofe at the bottom remam there the whole day; 

 but having lengthened themfelvcs a little (for hitherto they are doubled 

 up) they mount at intervals to the mucus they had quitted, and are {ttn. 

 to feed upon it. The next day they acquire their tadpole form. In three 

 days more they are perceived to have two little fringes, thatferve as fins, 

 beneath the head; and thefe in four days after affume a more perfect 

 form. Now they feed greedily on the pond-weed j and, leaving their 

 former food, continue to fubfifl; on this till they arrive at maturity. 

 When ninety-two days old, two fmall feet begin to burgeon, near the 

 tail J and the head appears feparate from the body. The next day, the 

 legs arc confiderably enlarged j four days after, they refufc all vegetable 

 food ; their mouth appears furnifhed with teeth, and their hinder leg^s are 

 completely formed. In two days more the arms are completely pro- 

 duced ; the fkin divides on the back near the head, which paffes through 

 the divifion : the membrane, which fcrved for a mouth to the tadpole, is 

 drawn backward j the arms are projected; and the enveloping fkin, per- 

 petually driven backwards, at length quits the body : and now the frog 

 is every way perfeft, except that it dill conti-nues to carry a tail. In this 

 odd fituation the animal, refembling at once both a frog and a lizard, is 

 feen frequently rifing to the furface to bteathe. Thus it continues about 

 fix or eight hours, till the tail diminifhing by degrees, the animal appears 

 in its moft perfe(!;l: f^rm. 



So extraordinary is this transformation, that the food it fed on greedily 

 a few days before, is now rejedled ; it would even flarve if fupplied with 

 no other : from having fed on vegetables, it becomes carnivorous, and 

 lives entirely on worms and infe<5ts ; quitting its native element, thefe it 

 feeks on land. Ai; firfl, being feeble, and unable to bear the warmth of 

 the fun, it hides among buflies and under ftones ; but if a fhower refrefh 

 the earth, then multitudes quit their retreats, to enjoy the grateful hu# 



midity ♦ 



