100 Shufeldt, Osteology of Harris's Cormorant. [iNt^"oct 



At the anterior extremity of this })elvis of Nannopteriim there 

 will be observed the marked downward extension of the first 

 three vertebrae beneath the iha. The transverse compression of 

 them is very great, and all of the three haemal spines sent down 

 by them are much in evidence, forming, as they do, a very 

 striking feature of the pelvis, not only in this flightless Cor- 

 morant, but in the pelves of most of its relatives in the genus 

 Phalacrocorax. 



The posterior articular facet on the centrum of the 2ist 

 vertebra, or the hinder one of the two together-fused vertebrae 

 of the dorsal region of the column, is elongo-elliptical in outline, 

 with the major axis vertical, and the whole markedly concave. 

 This accounts for an ellipsoidal, convex facet on the anterior face 

 of the centrum of the 22nd vertebra, which, in the duly articulated 

 skeleton, fits accuratelj- into the concave one previously described. 

 This kind of articidation with facets of similar size and form — 

 an opisthocoelous one — also obtains in the case of the last dorsal 

 vertebra, and further accounts for the large, hemi-ellipsoidal 

 facet on the leading vertebra consolidated with the pelvis beneath 

 the ilia. 



Ventrad, in the deep and ample pelvic basin, in the case of 

 Nannoptenim, there is an unusual variation to be noted with 

 respect to the diapophysial braces thrown out on the part of the 

 two sacral vertehrce that brace the pelvic walls directly opposite 

 the antitrochanters. Sometimes these are both perfect and 

 strong (No. 19,628) ; again, the anterior one on the right side may 

 be abs.ent (Nos. 19,719, 19,720, and 19,721, ?) ; or the anterior 

 ones may be stout and the posterior pair slender (No. 19,722). 

 This, however, is a peculiarity that holds in the case of other, 

 or at least some other. Cormorants. 



In P. piinctatiis the pelvis is long and narrow, reminding one of 

 the bone in some of the Loons or Grebes, notwithstanding the 

 fact that all of its essential characters are strictly phalacrocoracine. 

 In it, however, the obturator space is very long and narrow, with 

 the pubic element bounding it below very slender, the distal, 

 thickened part of which makes a very close articulation with the 

 lower border of the ischium, which latter, at its postero-external 

 angle, is produced to mould itself upon it, and passing which, 

 the free extremity of the pubis is curved directly downwards and 

 inwards, and in no degree backwards. 



In nearly all Connorants of the genus Phalacrocorax the inter- 

 diapophysial foramina in the post-acetabular region, dorsad, are 

 large, and most often occur as far forward as the antitrochanters. 

 In them, too, the backward-extending process of the ilium, on 

 either side, fonning the mesial boundary of the " ilio-ischiac 

 notch," is short — much shorter in proportion than we find it in 

 Nannoptenim. 



The Sternum. — Harris's Cormorant has this bone fashioned 

 along the lines of the typical " raft " pattern, as will ever be the 

 case with any bird wherein the power of flight has, for many 



