HERPETOLOGY OF THE GRAND DUCHY OF BADEN. 17 



The quantities of small frogs aud toads sometimes seen covering 

 a large extent of ground has given rise to the notion that they have 

 been rained down from the clouds, whereas, in all probability, the 

 explanation given long ago by Eoesel is the correct one, viz., 

 that a sudden rainfall has caused them to quit the fissures of the 

 ground, where, before, they had been sheltering from the dryness. 

 In an old work of the seventeenth century, by one Gasparus 

 Schott, a Jesuit professor, the author gives his views on the 

 subject: — "Ranas ex putre pulvere* & imbre nasci notum est 

 omnibus, ut ipsemet non semel vidi" ; and, later on, " Cum ipsa 

 subinde pluvia decidunt, in nubibus generate. Testes habeo 

 oculatos, imo et oculos meos ! " But he does not always trust to 

 his own powers of observation. Thus, after discussing at great 

 length the vexed question whether the Salamander can exist in 

 fire, and weighing the probabilities on either side, he comes to 

 the conclusion : — " Salamandra aliquamdiu in igne vivit, — at 

 deinde moritur." 



It has been observed that the young of this and other nocturnal 

 batrachians display much more agility, in various ways, than the 

 adults. When it is found that, in addition to this, they lead a 

 diurnal — i. e. more natural — life, we are led to consider whether 

 the ancestors of the race have not been forced, in the course of 

 time, to assume their present concealed habits, presumably for 

 the sake of protection. The colour affords further confirmation 

 of this hypothesis : there has been a simultaneous acquisition of 

 nocturnal tints in place of the original brighter ones now confined 

 to the immature condition. Their present sedentary mode of 

 existence has therefore resulted in a partial muscular atrophy, 

 similarly as unwonted exercise will induce hypertrophy of parts. 

 In this and many other instances a more systematic study of 

 ^ the ontogenetic development would doubtless yield much evidence 

 ^ of the gradual differentiation, through increased use or disuse, of 

 ^ allied races. This is certainly one of the most fertile provinces 

 of Natural History, and, being comparatively unexplored, offers 

 special attractions to the biological speculator. It is seen that 

 the young of many species possess a greater variety of capacities, 



* This is akin to the idea expressed by some peasants in the Auvergne, 

 who, misled perhaps by external resemblances, imagine that the Viper is 

 formed spontaneously out of the dung of horses and cattle. 



ZOOLOGIST. — JAN. 1892. C 



