476 



BIRD. 



use these in steering their course, in supplement to 

 the tail, which is, generally speaking, short. 



The example above given must be considered not 

 as an average of the crane family, as the storks do 

 not strictly belong either to the cranes or to the 

 herons, though they resemble both ; but it is a 

 tolerable average of the sternal apparatus of Cuvier's 

 sub-order cultrirostres. 



Intermediate between these and the grallidse,which 

 include the pressirostres and longirostres of Cuvier, 

 which have much less difference in their haunts and 

 style of flight, and consequently in their sternal 

 apparatus, than in their bills, there are some species 

 or genera, which require distinct notice. These are the 

 ibises and the spoon-bills, which are more discursive 

 than almost any members of the crane or heron 

 families. The birds which may be considered as 

 forming this group do not suit well with the genera 

 with which they are usually classed according to the 

 bill. That of the spoon-bills is not in the coulter or 

 knife-shape, as may be seen by looking back at a sketch 

 of it given on a former page ; while that of the ibis, 

 though it resembles in shape the bill of the curlew, 

 and certainly deserves the epithet " long," is not of 

 the same texture with the generality of those bills of 

 which length has been taken as the distinguishing 

 character. The genus tantalus, which resembles ibis 

 in many particulars, has the bill straight ; and there 

 are various other genera included in the cultrirostres 

 of Cuvier which have bills so totally different from 

 each other that they cannot properly be brought into 

 one group from the structure of that organ. 



With regard to the habits of these birds, and more 

 especially those of the genus ibis, it may not be irre- 

 levant to mention that they have long got credit for 

 being destroyers of poisonous serpents, and according 

 to the story were, on this account, deified by the 

 Egyptians ; but this habit is very doubtful, beetles are 

 more likely food for them, and poisonous serpents are 

 not numerous in their haunts. 



The general habits of the ibis, tantalus, and spoon- 

 bill so much resemble each other, and they are all so 

 perfectly similar in their sternal apparatus, that they 

 belong perhaps more naturally to the same group 

 than almost any other genera of birds. Their sternum 

 is short, broad, and deep, with the keel much pro- 

 duced, and altogether indicating a capacity of powerful 

 and continued flight. It is pointed anteriorly so as 

 to afford firm basis to the coracoids. The keel is a 

 little concave anteriorly, but convex on its under side. 

 It is nearly of the same breadth throughout ; bears 

 six ribs on each side, the sides being concave when 

 viewed laterally, and the posterior portion is divided 

 by two notches of moderate depth towards each 

 angle, the central process being longer and much 

 stiffer than the lateral vcies. The coracoids are short, 

 strong, well-set, much enlarged both at their bases 

 and at their heads ; and the clavicle forms a perfect 

 semi-ellipse, thickened at the shoulder-joints, and 

 generally united to the angle of the sternum. The 

 scapular is small-pointed at its extremity, and very 

 slight and curved. The strength of this apparatus is 

 obviously directed towards, or concentrated on, the 

 shoulder-joint ; while the comparative shortness of 

 the sternum, and the flexibility of its posterior angles 

 in consequence of the notches, give free scope for the 

 motion of the legs, which are in all the species long 

 riiul well adapted for walking. 



The following lulf-sizcd figures of the sternal 



apparatus of the glossy ibis (falcincllus), which some 

 times, though rarely, makes a dash into this countn 

 on its migrations, will serve as an example of thosi 

 very singular birds. 



Glossy Ibis. 



Sterna of the Totipalmee. These birds, which maj 

 perhaps be considered as, in habit, taking up tin 

 system after the herons, have considerable diver 

 sity in their haunts and modes of life. Some, as th( 

 albatross, are almost habitually on the wing ove: 

 the sea, while others, as the cormorants, are less 

 discursive, resort sometimes to the fresh waters, anc 

 occasionally perch upon trees ; but they all agree ir 

 finding the greater part, if not the whole, of theii 

 food in the waters, and descending upon it on th< 

 wing, instead of getting it by wading or by walking 

 as is the case with the groups last mentioned. Hence 

 in all the varieties, they have a sternum well adaptet 

 for flight ; but it also combines another character 

 which will be better understood after examining the 

 following figures of the sternal apparatus of the com 

 mon cormorant, which are given of half the linea 

 dimensions of nature. 



Cormorant. 



It is however in the next figure, which is the pro- 

 file on the same scale, that the peculiar modification ol 

 the sternum of these birds is best seen. 



Upon examining the following profile figure, it will 

 be found that this bone presents a still more power- 

 fully-resisting arch to the front than that formerly 

 alluded to in the divers. The anterior edge of the 

 keel, the coracoid, and the clavicle, form a complete 

 egg-shaped structure, with its narrow end in the head 

 of the last bone, where it is greatly increased in 

 breadth, and consequently in firmness of resistance ; 

 while, from the manner in which the head of this bone 

 is formed, any strain given upon the more advanced 



