[ 84 3 



ferent feafons in the year, as is more particularly 

 feen in the ardic regions •, not to mention that of 

 the fexes in almoft all kinds. Our author therefore 

 does not truft to this^ wherever a more permanent 

 mark can be found. It muft, however, be con- 

 fefied, that in too many inftances, it is necefTary 

 to truft entirely to this diftin6tion, howfoever un- 

 liable. The form of the tail^ as it happens to be 

 eveuy cuneated^ or forked^ is an excellent and firm 

 note in the Parrot genus its length, as Jhorter or 

 longer than the body, is of great fervice. In others, 

 the colour of the beaky a naked or crefted head^ con- 

 tribute to form the note of diftindlion. And in 

 fine, nature has ftamped upon others fome pecu- 

 liarity, which points them out immediately as, 

 the receptacle of the lower mandible, in the Pelican ; 

 two long tail-feathers^ in the Tropic-bird-, the di- 

 riedion of the mandibles in the Crofs-beak^ &c. 

 Among the common marks, none more frequently 

 occur than the differences of colour in the quill- 

 feathers and thofe of the tail. This clafs compre- 

 hends upwards of 930 fubjedls. 



Clafs III. AMPHIBIA. 



This clafs is fo called by Linn^us, not becaufe 

 all the fubjeds of it are, ftridtly fpeaking, ca- 

 pable of living either in air or water ; but prin- 

 cipally from their power of fufpcnding or per- 

 forming the fundlion of refpiration in a more ar- 

 bitrary manner than other anim.ais. This clafs is 

 divided into four orders : 



I. REPTILES. Reptiles. Amphibious ani- 

 mals breathing through the mouth by means of 



lungs 



