28 



"The Common Frog exercises little discrimination in the choice of 

 water in which to deposit its ego's, provided it be not brackish, often 

 spawning in temporary winter pools which are sure to dry up before 

 the time at which the larvcis have completed their metamorphosis, 

 or on the edge of a pond where, the level of the water falling after 

 dry weather, the egg-clumps remain stranded. No doubt the frogs 

 are attracted to the shallow, slanting borders in preference to the 

 deeper parts with abrupt banks by the comparative warmth of the 

 water under the sun-rays of late winter or early spring, with the 

 unfortunate result which may be witnessed almost year after year 

 in some places, when, following a spell of dry weather, the borders 

 of ponds are covered with the stranded jelly-like masses of frog- 

 spawn drying away in the sun before the liberation of the larvse. 

 On my country rambles in the end of March or the beginning of 

 April, I have often rescued the progeny of many frogs by removing 

 such doomed egg-masses from these fatal beaches to deeper water 

 close by, which the mother would have chosen had she been gifted 

 with the instinct possessed by the Common Toad. 



" The migrations of the Common Frog towards the water must 

 take place, to a great extent, in the autumn, as many, perhaps the 

 majority of individuals, hibernate bui'ied deep in the mud at the 

 bottom of ponds, sluggish but not dormant as in some higher 

 animals. Some years ago, just before Christmas, after a period of 

 severe frost, which had lasted more than a week, I was walking on 

 the ice of a small and shallow pond in Belgium, when my attention 

 was drawn to a bright red creature, first taken for a gold-fish, 

 moving under the ice, which very nearly extended to the bottom of 

 the pond ; this was a Common Frog, and on looking closer, I dis- 

 covered hundreds of others, less conspicuous owing to their yellowish, 

 brown, or olive colour. Some were very handsome specimens, 

 which I wished' to secure. A pick-axe was fetched from a neigh- 

 bouring farm and a hole made in the ice, through which I could 

 introduce my arm and reach the bottom ; but the frogs were so 

 active that they swam away and not one could be caught. I decided 

 to return to the pond after the thaw, which I did, but no more frogs 

 were to be seen ; they had evidently retired to their hibernating- 

 qaarters in the mud and in holes under water. The reason why 

 they came out when the pond was frozen nearly to the bottom, 

 must be attributed to the reduced oxygen in the water, which made 

 the frogs, breathing as they do under such conditions chiefly by the 

 skin, feel uncomfortable and desire to escape. 



"The Counnon Frog is the earliest breeder among European 

 Batrachians, spawning taking place in the South of England from 

 between the end of January and the end of March, the date depend- 

 ing almost entirely on the temperature and therefore varying 

 considerably from year to year. Should the winter be a mild one, 

 the breeding may be over by the middle of February ; recurrence of 

 cold weather after the frogs have begun spawning may cause them 



