PELVIS. 



169 



coccyx has five pieces in the Pheasant and 

 Turkey, and, in the latter, is said not to be 

 perforated for the spinal chord. In the Pea- 

 cock there are eight pieces, and the terminal 

 bone is a horizontal oval plate to support the 

 radiating feathers. In the tailless Manx va- 

 riety of the common Fowl, the coccyx is 

 borted into a single tubercular projection. 



The ilia and ilio-sacral ossifications are broad, 

 and the ischia long, divergent, and widely 

 expanded posteriorly into a very broad sacro- 

 sciatic element, much hollowed out in the 

 pelvic cavity, and enclosing a large foramen 

 (see fig. 105. /). This is especially marked in 

 the Crown Pigeon, Bustard, Crested Curassow, 

 and Guan. The pubes are long, and generally 

 unite with the ischia to complete an elongated 

 obturator hole (p). In the Dove, the pubes 

 and ischia are united in their whole length, and 

 the foramen is obliterated, while in the Crested 

 Guan and Trumpeter it is subdivided into an 

 anterior and posterior portion, as in the 

 Ostrich and Rhea. 



In the Grallatores the sacrum is broad, and 

 composed of from ten to twelve pieces, but in 

 the Oyster Catcher there are fifteen. In the 

 Snipe the transverse processes are more or 

 less separated. The coccyx is in seven or 

 eight pieces. 



The ilia and ischia are shorter and broader 

 than in the Natatores, the former being placed 

 more parallel to the spine, crossing it at 

 about 165 ; and the latter forming an ilio- 

 ischial angle of 160. The inter-cotyloid dis- 

 tance is very great, especially in the gigantic 

 Crane, but in the Stork and Bittern the whole 

 pelvis is smaller and more contracted. The 

 pubes are long, diverging, and parallel to the 

 ischia, especially strong in the Aptenodytes ; 

 and enclosing often a large obturator foramen 

 by coalescing with the ischia. In the Stork, 

 Ibis, and Flamingo, however, there is no such 

 union. 



In the Scansores, the sacrum of the Parrot 

 is short and very broad, the ilia and ischia 

 also short and broad, as well as the ilio- 

 sacral and sacro-sciatic bones, inclosing a small 

 foramen ; and the pubes, uniting with the ischia 

 in two distinct places, encloses a subdivided 

 obturator foramen. The coccyx of the Tou- 

 can is long and very flexible. 



In the Passeres, the sacrum is composed of 

 from ten to thirteen pieces ; but in the King- 

 fisher there is but eight. The coccyx is in seven 

 to nine pieces, very flexible in the Pies and 

 Swallow; and in the Woodpecker very strong, 

 and supporting on its anterior aspect, near the 

 extremity, a remarkable, round, concave disc, 

 formed by the coalescence and spreading of 

 several of the bones anteriorly. Its use is 

 evidently to support the body by being ap- 

 plied to the stems of the trees to which it 

 clings in the pursuit of its prey and attaching 

 the spreading tail feathers. The ilia, ischia t 

 and pubes are slender in the Passeres, 

 and the obturator foramina generally incom- 

 plete. 



The pelvis of the Raptores, or Birds of prey 

 (fig. 107.), is narrower, the bones more com- 



pact and massy, and less expanded than in the 

 foregoing orders. 



The sacrum is narrow, and composed gene- 

 rally of eleven bones, which, in the Sparrow- 

 hawk, are ankylosed to the last lumbar ver- 

 tebra. The coccyx is straight, and in seven or 

 eight pieces, with a large and blade-like ter- 

 minal bone directed dorsally (a). 



The ilia (6) are proportionally larger, and 

 project more dorsally than in the other orders, 

 overlapping the spine with elongated wings, 

 concave externally ; and a strong tapering ilio- 

 sacral plate (g), which is directed much down- 

 wards, as well as backwards, to unite with the 

 sacro-sciatic plate (e) behind the foramen, so 

 as to cross the line of the coccygeal bones 

 almost at a right angle. The ischia (c) are 

 rather short, strong, and convergent posteriorly, 

 where they terminate by a long and pointed 

 spine (i), with a strong but narrow sacro- 

 sciatic ossification enclosing a small foramen 

 (/&). The ischio-sacral cotyloid buttresses (/) 

 are largely developed, The ilio-ischial angle 

 is remarkable in being reversed or turned for- 

 ward to a marked extent, 130 in the Eagle, 

 and 145 in the Owl (see Jigs. 107. and 112. 



Fig. 107. 



Pelvis of the Eagle, lateral view, showing the reversed 

 ilio-ischial angle. 



11.), a peculiarity to which we have seen, 

 as before mentioned, a tendency in the peivif* 



