198 Shufeldt on the Os Prominens in Hawks. 



Mv attention was called to the fact several months ago, while 

 engaged in preparing the skeleton of a fine specimen of Circus 

 hudsonius which I hud secured for that purpose. The bird in 

 question had beer, allowed to macerate for a long time, as a dis- 

 articulated skeleton alone was desired, so that disintegration 

 of the soft parts was very complete and the bones sank to the 

 bottom of the vessel containing my Hawk. Upon collecting these 

 together and assorting them I found a pair of ossicles that I 

 could not exactly account for, nor conceive as to which part of 

 the bird's skeleton thev rightfully belonged ; of course the verte- 

 bral column, sternum, ribs, and pelvis could, one and all, be 

 immediately discarded ; first in order, naturally came the carpus 

 and tarsus both of which were carefully examined, an examina- 

 tion that at the time 1 am free to confess threw no further light 

 upon the subject, for the extremities of the long bones seemed to 

 possess nothing that approached the appearance of additional 

 facets for articulation, and the two free ossicles of the carpus 

 seemed to exhibit all their usual characteristics as irregularly 

 formed bonelets, not differing materially from their homologues 

 in other birds of powerful flight. From the bony remains of my 

 disjointed Marsh Harrier, I turned to the authors and authorities 

 but only after thorough search through the works of those then 

 at my command did I find that mv labors were to terminate as 

 already cited. Nothing was revealed or described that assisted 

 me in the elucidation of such an unsuspected problem. My 

 fowling piece and another specimen was the only and best 

 resort left. but. as we all know . when a certain species of the 

 class Aves becomes particularly desirable and must be had at 

 once, no matter how common it may be, that bird suddenly 

 develops a remarkable shyness, to say nothing of rarity, and 

 such was the case here, for fully a month elapsed before a dupli- 

 cate was taken ; but it came at last in the shape of a fine adult 

 female of the species already considered, and she was eagerly 

 carried to my study. 



My first suspicions were the first to be satisfied, and to this end 

 I made an incision, carried only through the skin, around the 

 shoulder, then carefully removed the integuments, allowing the 

 quills of the primaries to remain, from the entire wing. This 

 being successfully accomplished, the following condition of 

 affairs at the wrist joint at once were disclosed to me, and care- 

 fully noted. 



