1044 ME, W, P, PYOEAFT OjST THE [DeC. 19, 



B. Greatest width of sternum across posterior lateral processes more than i — 

 sometimes equal to — its whole length ; metasteruum deeply notched, not 

 projecting so far back as ends of posterior lateral processes ; coracoid 

 groove very deep ; no spina externa ov interna ; no precoracoid ; posterior 

 lateral processes of coracoid short and blunt ; scapula with long acromion. 



PODICIPEDID^. 



D. Peltic Giedle. 



Greatly elongated and compressed laterally behind the acetabulum ; closely 

 resembles that of the Cretaceous Hesperornis, and differs entirely from that of 

 any other living Carina! e bird, the postacetabular ilium being represented by 

 a nearly vertical plate of bone ; synsacrum almost styliform ; pleurostea 

 caudad of acetabulum wanting ; parapophysc^s vestigial. 



A. Free end of pubes spatulate Colyjibid.*;. 



B. Free end of pubes not spatulate PoDiciPEDrn^. 



E. Pectoeal Limb. 



The bones of the wing are relatively long; the humerus has a moderately 

 well-developed delto-pectoral crest, the coraco-humeral groove takes the form 

 of a deep pit ; there is a shallow fossa for the hrachinlis intermis ; the 

 fossa subtrochantericus is blind. The forearm is nearly or quite as long as the 

 arm. Mc. III. is long, slender, and runs parallel with Mc. II. 



A. Carpo-metacarpus much elongated ; Mc. I. vei-y long, ^ as long as Me. II. : 



manus as long as forearm Corymb id^e. 



B. Carpo-metacarpus not greatly elongated ; Mc. I. very short ; manus shorter 



than forearm Podicipedid^. 



P. Pelvic Limb. (Figs. 1-3, pp. 1038-9.) 



Femur very short; tibio-tarsus with an enormous cnemial crest; farso- 

 metatarsus laterally compressed ; outer toe longest ; ungual phalanges much 

 flattened. 



A. Cnemial crest as long as or longer than femur ; fibula extending downwards 



to the tarsus, or very nearly so ; the ecto-trochlear foraujen of tarso- 

 metatarsus tubular ; hypotarsus simple Colymbid-e. 



B. Cnemial crest shorter than femur ; fibula terminating near the lower 



\ of the leg ; hypotarsus simple ; ectotrochlear foramen in the form of 

 a groove PodicipedidjE. 



xii. List of Woeks eefeeeed to oe consulted. 



1. Beddaed, p. E. — Structure aud Classification of Birds, 1898. 



2. Beandt, J. P. — Beitrage zur Kenutn. der Naturgesch. der 



Vogel. Mem. Acad. Imp. des Sciences St. Petersbour-g, 

 ser. vi. vol. iii. 1839-40. 



3. CouES, E. — The Osteology of the Colyrnbm torquatus; with. 

 Notes on its Myology. Mem. Bost. Soc. Nat. Hist. vol. i. 

 part ii. 1867, pp. 131-172. 



