EEPTILES. TOADS. 67 



This morning I saw the golden-crowned wren,* whose 

 crown glitters like burnished gold. It often hangs like a 

 titmouse, with its back downwards. * 



LETTEE XVII. 



TO THE SAME. 



Selboene, Jrnie 18, 1768. 

 Deae Sib, — On Wednesday last arrived your agreeable 

 letter of June the 10th. It gives me great satisfaction to 

 find that you pursue these studies still with such vigour, 

 and are in such forwardness with regard to reptUes and 

 fishes. 



The reptiles, few as they are, I am not acquaiated with 

 so well as I could wish, with regard to their natural history. 

 There is a degree of dubiousness and obscurity attending 

 the propagation of this class of animals something analagous 

 to that of the cryptogamia in the sexual system of plants ; 

 and the case is the same with regard to some of the fishes, 

 as the eel, Ac. 



The method in which toads procreate and bring forth, 

 seems to be very much in the dark. Some authors say that 

 they are viviparous ; and yet Hay classes them among his 

 oviparous animals, and is silent vrith regard to the manner 

 of their bringing forth. Perhaps they may be ia-a /xeV mora- 

 Koi, £|iB 8e fmoTOKot, as is known to be the case vpith the viper, t 



The copulation of frogs (or at least the appearance of it — 

 for Swammerdam proves that the male has no penis inirans) 



* It is surprising that this feeble diminutive bird should brave our severest 

 ■winters. — Ed. 



•f* Toads are oviparous. Mr. Bell of London, a zealous ophiologist, has 

 lately confirmed the fact recorded by Schneider, that toads devour the skin 

 wliich they shed. In one instance, he witnessed the whole process of the 

 shedding of the cuticle : it became divided longitudinally along the back and the 

 abdomen ; by the action of the hinder leg on one side, the skin was detached 

 as far as tlie fore-leg ; the same operation was next effected on the other side. 

 The loosened exuvitB were then drawn forward, by the combined action of the 

 mouth and of the anterior legs, and were immediately swallowed. — Zool. 

 Jour. Mr. Bell adds, that in others of the bcUrachian reptiles, the ranos and 

 salamandrCE, no swallowing of the exmnce took place. — W. J. 



r2 



