EXPEDITION TO FUNK ISLAND. 



523 



It is singular that the closest correspondence between the curves rep- 

 resenting right and left sides should be exhibited by the diagrams giv- 

 ing the measurements of the femur, the most variable bone — while the 

 least harmony is found among the humeri, bones which differ least 

 among themselves. 



This discrepancy is caused by an uuusuall^'^ large number of left hu- 

 meri having a length of llO™'", but on the whole the curves follow one 

 another very closely, the maximum point being reached with great una- 

 nimity, and the sizes of the bones decreasing or increasing quite regu- 

 larly from that. 



From the examination of this large amount of material it would seem 

 that considerable variation may exist in the size of individuals, that the 

 number of ribs may be slightly inconstant and that a certain amount 

 of variation may be found in the development of the various processes 

 of the vertebrte. On the other hand the skull, sternum, and pelvis 

 afford very substantial comparative characters. 



In regard to the question of size, it can be said that there is nothing, 

 as in the case of Didine remains, to indicate sexual difference in this 

 particular, for between the largest and the smallest bones may be found 

 all intermediate grades. 



This, however, is what might have been expected, for the Alcidce 

 present but slight sexual variations in size, while Professor Newton 

 has pointed out a good reason for the slight amount of proportional 

 variation in the fact that the bones represent individuals from the same 

 epoch and locality, and not those separated from one another by long 

 intervals of time or space. 



Measurements, in millimeters, of Crania of the Great Auk. 



18233. 



Greatest length between perpendiculars. . . 



Greatest parietal breadth above articula- 

 lation of quadrate , 



Greatest post frontal breadth 



Height from basi-sphenoid to frontal 



Height of culmen immediately in front of 

 nasal opening 



Length from posterior end of occipital 

 ridge to root of intermaxillary 



Length of mandible 



Length of mandibular symphysis 



61 



139 



23 



