100 



GENERAL ORNITHOLOGY. 



■A velvety pile, or they may radiate in a circle from a given point, as from the eye iu most owls, 

 where they form a disc. 



Iu the foregoing paragraph I only mention a few styles of crests, chietly needed to be 

 Icuown iu the study of our birds ; but should add that there are many others, with endless 

 modifications, among exotic birds ; to these, however, I cannot even allude by name. Peculiar- 

 ities of nasal feathers, and others around the base of the biU, are noticed below. Forms of crests 

 are illustrated by many of the figures given pussiin in the present work. 



2. OF THE MEMBERS: THEIli PAHT.V AKD OJtGAyS. 

 I. THE BILL. 



The BiU (Lat. rostrum) is hand and month in one : the instrument oi prehension. As 

 hand, it takes, holds, and carries food or other substances, and in many instances, feels ; as 

 mouth, it tears, cuts, or crushes, according to the nature of the substances taken ; assuming 

 the functions of both lips and teeth, neither of which do any recent birds possess. An organ 

 thus essential to the prime functions of birds, one directly related to their various modes of life, 

 is of much consequence in a taxouomic point of view ; yet its structural modifications are so 

 various and so variously interrelated, that it is more important in framing genera than faniUies 

 or orders ; more constant characters must be employed for the liigher groups. The general 

 shape of the bill is referable to the cone; it is the anterior part of the general cone that we 

 have seen to reach from its pt)iut to the base iif the skuU. This shape confers the greatest 

 strength combiued witli the greatest delicacy ; the end is fine to apprehend the smallest cdijects. 

 while the base is stout to manipulate the largest. But in no bird is the cone expressed with 

 entire precision ; and, in most, the departure from this figure is great. The bill always con- 

 sists of two, the upper and the lower 



Blandibles (tig. ijli), which lie, as their names indicate, above and below, and are sepa- 

 rated by a liorizimtal fissure, — the mouth. Each maudible always consists of certain project- 

 a b c (I e f II ii'g skull-bones, sheathed with more or less horny int(>gument in hen 



of true skin. The fi'anic-work of tlie Upper Mandible is (chiefiy) 

 a bone called the interniaxinary, or better, in this case, the premax- 

 iUary. In general, tliis is a three-pronged or tripodal bone runuini; 

 to a ])oiut iu front, with the ujipermost prong, or foot, implanted 

 upon tlie forehead, and the other tM'o, lower and horizontal, running 

 into tlie sides of tlie front of tlie skull. The seaft'old of the Under 

 Maudible is a compound bone called inferior maxillari/ ; it is U- or 

 V-sluiped, with the point or convexity iu front, and the prongs run- 

 ning to (ither side of the base of the skull behind, to be there mov- 



cuUiien ; c. iiMP.ll fossa; </, , , , ■ , rm * i -xi , ■ i .. , 



nostril; e (see l.elow);/, gapo! '^"'^ hiuged. 1 hese two boues. With certain accessory bones of the 

 or whole eommissuial line: </, upjier nuindible, as the ^)n/«fe bones, etc., together with the honiv 

 investment, constitute the Jaws. Both jaws, iu birds, are movahle : 

 the under, by the joint just meutioued ; the upper, either by a 

 joint at, or by the elasticity of the bones of, the forehead; it is 

 moved by a singular muscular and bony apparatus in the palate, 



dZ')!"ra!'irorilo"'ys; "" ^"''^'''''' ''"*''''^ "*' "'^'"''^ ^" S'^''''^ bcyoud, under head of Anatomy 

 goiiys; ;«, skieof uiulor man- (Osteology). Tlio motion of the upper uuuidible is freest and most 

 an.le; «, tips of mandibles. extensive in the parrot tribe, where both fronto-maxillary and 

 palato-maxillary sutures exist. When closed, the jaws meet ;ind fit along their apposed edges 

 or surfaces, iu the same mauner and for the same purposes as the lips and teeth of man or 

 other vertebrate animals. All bills, thus similarly constituted, have beiai divided into 



m } J: j i 

 Fio. 26. — Tarts of a Bill, 

 a, side of upper mandible ; b. 



rictns; h, comnii.ssural i)oint 

 or angle of the mouth ; i. ra- 

 mus of under jaw ; ,/, tonna of 

 under mandible (the rel'er- 

 ence lines e should have been 

 drawn to indicate the covre- 



