Reptiles. 827 



occurs, the tongue is instantly protruded and withdrawn, taking the 

 insect with it. The rapidity with which this movement is effected, 

 prevents its being seen how the tongue secures the insect, but it is 

 generally said to be by means of a viscid secretion diffused over its 

 tip. A worm is caught in the same way, but it sometimes happens 

 that it cannot be so easily swallowed as the insect, and it hangs 

 writhing and twisting about the mouth. But the frog rarely lets go its 

 hold, however much the worm may twist, but succeeds in swallowing 

 it, in just the same attitude in which it took it. While in the act of 

 taking its prey, the body, following the motion of the tongue, slightly 

 falls forwards, and again immediately regains itself, as the tongue re- 

 enters the mouth. The frog always prefers living food, and this I 

 have sometimes thought is the reason it so intently watches its prey 

 before it takes it, — to see it move, to prove its life. 1 have seen an 

 insect, between two stones, watched by a frog for nearly an hour toge- 

 ther, and although it has repeatedly moved, yet the frog has not 

 attempted to catch it, as if conscious it was beyond its reach. It has 

 given it up in despair, but loath to leave it, has again and again re- 

 turned to the charge. The whole process is one of much interest. 

 The most ravenous period of the year to the frog, is just as it has left 

 its hibernating retreat. This, according to authorities, is after the 

 cold winter is passed ; for they are represented as retiring to their 

 hibernating retreats on the approach of winter, and passing all that 

 gloomy period in perfect torpidity. This, however, is not the case in 

 Cornwall ; for the period of the greatest activity is in the depth of 

 winter. This opinion is deduced from repeated observations from 

 1833 to the present year. In 1833, tadpoles were common in all 

 ditches and road- side pools, as early as February ; in 1834, 1835, to 

 1837 and 1843, the ova were generally observed as early as the 21st 

 of December ; and in every year, before the 1st of January. At this 

 period I have caught the old animals ; and in 1842 I saw many scores 

 actively swimming about in December, so that no doubt could arise 

 as to the identity of the spawn. On several occasions the cold was 

 so great, that the masses of ova were enclosed in ice, and frozen, so 

 that a blow would fracture them, like so much glass. As the months 

 of December, January, and February, are generally the coldest in the 

 year, it does not seem probable that they would leave their hiber- 

 nating retreats at these periods, if hibernating depended entirely on 

 cold. It is not unfrequently that we see both frogs and tadpoles 

 actively moving about under the ice covering the pools. At this 

 season the food is chiefly worms ; but the insects are evidently their 

 favourite food, and these they swallow whole and alive. 



