38 Shufeldt, Anatomy of the Passenger Pigeon. [.Jan. 



which, to a less degree, is the case with the rounded or convex 

 anterior contoural boundary. On the dorsal aspect there is a deep 

 concavity, which allows the liver to fit itself upon the supero- 

 anterior surface of the gizzard. 



The right and left bile ducts were not in evidence, and the various 

 divisions of the peritoneum could not be worked out entirely. 



Coming to the heart, I find it to have an extreme length of 23 

 millimeters, and a transverse diameter, above the ventricals, of 14 

 millimeters. I examined with great care all the vessels entering 

 and leaving its several cavities and their main branches; they are 

 identically the same as they occur in Columba lima, as described by 

 the late T. Jeffrey Parker in his admirable text-book entitled "A 

 Course of Instruction in Zootomy (Vertebrata)," on page 241, 

 Fig. 56. There is every reason to believe that the internal anatomy 

 of the auricles and ventricles of this heart of the Passenger Pigeon 

 agree, in all structural particulars, with the corresponding ones in 

 any large wild pigeon, as for example C. fasciata. I therefore did 

 not further dissect the heart, preferring to preserve it in its entirety, 

 — perhaps somewhat influenced by sentimental reasons, as the 

 heart of the last " Blue Pigeon " that the world will ever see alive. 



With the final throb of that heart, still another bird became 

 extinct for all time, — the last representative of countless millions 

 and unnumbered generations of its kind practically exterminated 

 through man's agency. 



Were I to go as far as I could into this subject of the anatomy of 

 the Passenger Pigeon, my collected observations would afford 

 matter for several good-sized volumes. Even the mutilated mate- 

 rial before me might furnish several chapters on the myology of 

 this species; on the circulatory system; the nervous system; 

 histology of the structures, and a great deal more besides. 



In any group of vertebrates, birds included, it is always an ad- 

 vantage to have published the entire morphology of some particular 

 species of a group, as for example a typical pigeon of the genus 

 Columba. Then, with respect to the morphology of species be- 

 longing to genera evidently closely related to Columba, it will but 

 be necessary to make record of enough, with respect to their minute 

 and gross anatomy, to establish the fact that our investigations 

 have led us to a point where we can predict, with absolute cer- 



