The Transformation of t lie Mexican Axolotl. 617 



dry air of summer by burying in the ground, where 

 they undergo a summer sleep. This is the case 

 with the interesting Salamandrina Perspicillata* 1 

 and with the land-living Sardinian Triton, the 

 remarkable Euproctus Rusconii, Gen6, " (Triton 

 Platycephalus, Schreiber). With respect to Geo- 

 triton Fuscus I learn from Dr. Wiedersheim, who 

 has studied the life conditions of this, the lowest 

 European Urodelan, in its own habitat, that in 

 Sardinia it sleeps uninterruptedly from June till 

 the winter ; whilst on the coast of Spezia and at 

 Carrara, where it also occurs, it avoids the summer 

 sleep in a very peculiar manner. It makes use of 

 the numerous holes in the calcareous formation of 

 that region, and for some months in the year 

 becomes a cave-dweller. As soon as the great 

 heat occurs, often in May, it withdraws into the 

 holes, and again emerges in November during the 

 wet weather. In these lurking holes it does not 

 fall into a sleep, but is found quite active, and 

 its stomach, filled chiefly with scorpions, shows 

 that it goes successfully in search of food ; the 

 moist air of the holes makes k unnecessary for it 

 to bury in the earth. 



In the same sense it appears to me must be 

 conceived the fact that the solitary species of frog 



" See Wiedersheim, " Versuch einer gleichenden Anatomic 

 der Salamandrinen." Wiirzburg, 1875. 



a See Gene', " Memorie della Reale Acad. di Torino," 

 vol. i. 



