Australian Birds in the Collection of the Linnean Sucicti/. 267 



which it is designed to break. In speaking of the shortness of 

 this member, we measure the space between the rictus and tlie 

 apex, which in the birds to which we allude seldom equals the 

 distance between the mcnfui/i and the same point. On the 

 other hand, the remaining three subdivisions of the family have 

 a longer, and consequently a weaker bill. The under mandible 

 in particular becomes conspicuously elongated, the totnia or 

 cutting edges being sometimes nearly straight, and the depth 

 not equalling half the length. The bill thus assumes the gene- 

 ral form which is found among birds, and deviates from that 

 which appears peculiar* to this family. In some of these longer- 

 billed birds, which we are thus inclined to consider aberrant 

 among the Parrots, we shall have occasion to observe a devia- 

 tion also from the mode of feeding prevalent in the family by 

 the tongue partially superseding the use of the bill. Here we 

 may trace the tirst approach to the Ficida, Certhiadce, and the 

 honey-feeding Tenuirostres ; birds which form a conterminous 

 group immediately succeeding the present family of Psittacidce, 

 and of which the use of the tongue is the predominant cha- 

 racter. ; 



Accordino- to these views we shall consider the shorter- and 



* We know no other bird in which this peculiar construction is found, except tlie 

 Fratercula Arcticu, Briss., in which species the depth of the bill from the front to the 

 mciitiiiii is nearly equal to the length from the rictus to the ape.r. This analogical re- 

 semblance has given that bird the familiar name of Sea-Parrot. In some of the 

 Loriada' also we see an approach to the same depth and shortness of bill, but not an 

 equal developementof the character. And here also the name of Psittarostra, attached 

 to one of the groups, indicates the same analogy. We may observe, that the food of the 

 birds of this latter family is similar to that of the Parrots, and requires corresponding 

 powers of bill. When we speak of the height of the bills among birds, we do not take 

 into account those eminences which surmount the bills of some of the JJiicerida'. 

 These give an apparent rather than a real elevation to these members, and in no wise 

 mcrease their strength. 



2 M 2 stronger- 



