Shufeldt : Osteolo(;y or ihk Fi>amingoes. 321 



straight, and it is only at the proximal third that a very slight curving 

 backwards is to be noticed. The anterior surface of the shaft is 

 strongly grooved in the longitudinal direction for its entire length ; 

 this is also the case on the hinder aspect, but here it does not com- 

 mence for at least two centimeters below the hypotarsus, and gradu- 

 ally dies out, for a little more than that distance above the trochlea. 

 Laterally, either side of the shaft is flat and quite smooth. 



Passing to the proximal end of the bone, we find on the summit two 

 deep, subelliptical excavations, well separated mesially, for the recep- 

 tion of the condyles of the tibio-tarsus. In front, and standing di- 

 rectly between these on the anterior margin is the usual intercondyloid 

 process — here more than commonly conspicuous. Below this, an- 

 teriorly, the proximal beginning of the shaft is somewhat excavated, 

 and this concavity harbors a double tubercle for the insertion of the 

 tibialis anticus. Above these are two foramina! perforations, which 

 pass to emerge one upon either side of the hypotarsus behind — the 

 outer one being considerably larger than the inner one. Their course 

 is oblique from above downwards. The hypotarsal process is very 

 pronounced, but does not extend down upon the shaft behind. It 

 consists of two oblong plates, placed vertically as usual, with a wide, 

 deep passage between them for the accommodation of the tendons at 

 the back of the bone. Three trochlear processes are found at the dis- 

 tal end of the shaft, and they are all well developed. The middle 

 one, which is very large, is the lowest one on the shaft — the outer 

 one next, and the inner one is highest of all. The outer and inner 

 ones are produced well backwards, especially the inner one, which 

 holds in the main a decidedly posterior position. A deep notch 

 separates the middle and outer one, and above this notch, in the lon- 

 gitudinal groove there found, is the single, and large antero-posterior 

 perforating foramen for the anterior tibial artery. Very feebly marked 

 indeed is the articular facet, for the articulation of the free, first meta- 

 tarsal. Indeed, in the Flamingo, as in the Ibises, the latter is simply 

 hung to the bone by means of ligamentous attachments, without mak- 

 ing any true articulation, as it does in so many other groups of birds. 



Swans, Ducks, and Geese have, in so far as I have examined them, a 

 very different tarso -metatarsal bone from the one I have just described 

 for P. ruhcr. Upon comparing the latter, however, with the tarso - 

 metatarsus of Bcniicla canadensis, we find that the trochlear processes 

 at the distal extremities resemble each other in some particulars, but 



