1874.] ANATOMY OF THE PARROTS. 591 



In Cacatua galerita and C. leadbeateri it is present ; but it is 

 generally wanting in C. cristata, and has not been found in C. sul- 

 phured. . 



The above facts may be tabulated in a form which makes their 

 significance more readily apparent, by placing those together in which 

 a similar arrangement is observable. Thus there are : — 



1 . Parrots in which there are two normally situated carotids, no 

 ambiens muscle, a furcula, and an oil-gland — namely 



Aprosmictus, Loriculus, 



Calopsitta, Lorius, 



Calyptorhynchus, Palceornis, 



Eclectus, Prioniturus, 



Eolophus, Psittinus, 



E 0S) Tanygnathus, 



Licmetis, Trichoglossus. 



2. Parrots in which there are two normally situated carotids, no 

 ambiens muscle, no furcula, and an oil-gland— namely 



Agapornis, Geopsittacus, 



Euphema, Melopsittacus. 



3. Parrots with a left carotid only, no ambiens muscle, a furcula, 

 and generally an oil-gland — namely 



Cacatua. 



4. Parrots with two carotids (the left being superficial), an ambiens 

 muscle, a furcula, and an oil-gland— namely 



Ara, Nestor, 



Bolborhynchus, Pyocephalus, 



Ca'ica, Psittacus. 

 Conurus, 



5. Parrots with two carotids (the left being superficial), no ambiens 

 muscle, a furcula, and an oil-gland — namely 



Coracopsis, Pyrrhulopsis, 



Lathamus, Pyrrhura. 



6. Parrots with two carotids (the left being superficial), no ambiens 

 muscle, a furcula, and no oil-gland — namely 



Brotogerys, Pionus. 



Chrysotis, 



7. Parrots with two carotids (the left being superficial), no ambiens 

 muscle, no furcula, and an oil-gland— namely 



Cyanorhamphus, Psephotus, 



Platycercus, Psittacula. 



The true significance of these facts next requires attention ; and 

 the principle upon which all attempts at the formation of a satisfac- 

 tory genealogy or classiBcation of the suborder can be arrived at must 



