No. 2.] SHUFELDT ON THE OSTEOLOGY OF LANIID^. 355 



front ; the coracoidal grooves pass rouud laterally well beneath the 

 costal iirocesses, and merge into each other, mesiad, their point of meet- 

 ing being denoted by an elliptical depression, at the base of which we 

 occasionally find a single pneumatic foramen. The costal processes rear 

 themselves upwards, forwards, and outwards, being broad but thin lam- 

 inae of bone, impressed upon their posterior margins by the five trans- 

 verse facettes for the sternal ribs. The " body " is concave above, sloping 

 to a shallow, osseous gutter, lying in the mesial plaiie directly over the 

 keel; beyond, in this groove we observe a few scattered foramina for 

 the admission of air to the more solid structures of this confluent hneiual 

 spine. Behind, the bone is one-notched on either side, cutting out lat- 

 eral processes with expanded posterior ends and a broad mid-xiphoidal 

 portion — the direct continuation of the sternal body — (Fig. 92). The 

 "carina" below averages about 7 millimeters at its deepest part; ante- 

 riorly it protudes as a rounded carinal angle, from which point its inferior 

 boundary sweeps backwards by a gentle convex curve to terminate in 

 a diminutive triangular space at the middle of the xiphoidal process 

 beneath. 



The sides of the keel present for examination well-defined subcostal, 

 pectoral, and carinal ridges ; the latter falls on either side from the base 

 of the manubrial jirocess to near the carinal angle, just within the bor- 

 der, and sometimes has a thickened backward branch starting from its 

 lower end. The confluent pelvis, in common with the majority of pas- 

 serine birds, has that strikingly angular outline, due largely to sharpened 

 borders and outstanding spiny processes. There are ten vertebra? in 

 its "sacrum," all unusually firmly fused together, vacuities only occa- 

 sionly occurring among the diapophyses of the ultimate few, three or 

 four at most. The pre-acetabular region of the ilia on either side is 

 deeply concave, this concavity being carried up over the anti-trochanters 

 to terminate in shallow grooves over the ischiatic foramina. The greater 

 share of this surface looks almost directly outwards and only slightly 

 upwards. The ilio-neural canals are divided by the confluent spines of 

 the first four or five vertebrae, they var^- in width in different individuals, 

 and terminate at points opposite the cotyloid cavities, at which point 

 the neural spine suddenly becomes compressed, or rather annihilated, and 

 the sacrum sustains a flattened surface to the ultimate boundary of the 

 bone. The post-acetabular regions are of about one-third the extent of 

 the surfaces anterior to the cotyloid rings ', they are produced behind in 

 strong and clubbed processes, the outer margins of which are the termi- 

 nations of the gluteal ridges or lines continuous with these ridges; these 

 surfaces are convex and narrowed by the encroachment of the broad 

 sacrum (Fig. 103). 



Laterally the ilium overhangs the extensive and elliptical ischiatic 

 foramen, which is bounded in front by the anti-trochanter, directed back- 

 wards and slightly outwards; the cotyloid ring is markedly circular and 

 but little difference exists between the diameters of its inner and outer 



