l86 Shufeldt, Material for a Study of the Megapodiidce. [j^f"}",,. 



them the anterior third of the vertically compressed lamina that 

 caps the co-ossified " crista sterni." Posterior to this, the ilio- 

 neural canals are widely open, so that ^the double row of inter- 

 diapophysial foramina may be seen among the anterior sacral 

 vertebrae. Back of this again the sternum is broad and all in 

 one smooth plane, with only a few minute foramina to be seen 

 in it at its widest part. These foramina appear again, in three 

 pairs and of considerable size, among the last four sacrals, next 

 to the inner margin of the ilium upon either side. 



The postacetabular portion of an ilium is extensive, very 

 smooth, and bvit very slightly convexed ; the posterior endings 

 extend beyond the sacrum, so that, in the articulated skeleton, 

 an entire free caudal vertebra is within the recess thus created 



(fig- 44)- 



There appear to be i6 vertebrae in the pelvic sacrum, which 

 would make 41 for the whole spinal column, plus the pygostyle. 



On lateral view of the pelvis there are a few points to be noted. 

 There is a large " ischiadic foramen," which is acute ovate in 

 outline, the point being posterior. Below, and back of this, there 

 is a large, smooth, almost flat area, with vertical, sharp linear 

 border behind, all of which is furnished by the ischium. Interiorly, 

 the border is also sharp and concave ; it bounds the very consider- 

 able obturator space. This latter is formed by the long, slender 

 post-piihic style below, the latter projecting beyond the ischium 

 posteriorly. The small " obturator foramen " is of an elliptical 

 outline, and posteriorly communicates with the obturator space. 

 Viewed upon its ventral aspect, it will be seen that the leading 

 sacral vertebra closely resembles the last dorsal ; its transverse 

 processes are long and strong. Each reaches out to almost the 

 lateral border of the ilium upon either side, and there comes 

 extensively in contact with the inferior surface of the bone. The 

 transverse processes of the second sacral are much shorter and 

 smaller, being directed outwards, upwards, and forwards, to 

 likewise support the ilium on either hand from below. These 

 processes on the third sacral are nearly entirely aborted, though 

 they do reach the ihum upon either side. In the fourth and fifth 

 sacral vertebrae the diapophyses are of equal length, short, and 

 subcyhndrical in form ; they are thrown out at right angles to the 

 median plane, to abut against the under surface of the iha at 

 its narrowest point, just anterior to the capacious pelvic basin 

 possessed by this bird. 



The next three vertebrae have their transverse processes directed 

 upwards, backwards, and slightly outwards, to merge with the 

 sacral roof above. Following these, there are two vertebrae 

 which are usually reckoned as the true sacrals. The leading one 

 possesses very slender transverse processes directed backwards, 

 outwards, and sUghtly upwards, to terminate in bulbous outer 

 ends abutting against the ilium, The transverse processes of 

 the next following vertebra are shorter, with more expanded outer 

 ends for the iliac contact upon either side. These two bones are 

 in the transverse line between the acetabula. 



