192 MEMOIRS OF THE CARNEGIE MUSEUM 



a concavity that occurs immediately anterior to the articular cup. The other, ellip- 

 tical in form, is on the inner and lower aspect, and about 2 cm. beyond it. 



Each articular cup presents two concavities a central one and another occupy- 

 ing the inturned process of this extremity. Both have pneumatic foramina at their 

 bases. The mandibular angle behind is truncate and much compressed in the per- 

 pendicular direction. The under surface of one of these ends is perfectly smooth 

 and gradually merges into the inner and outer surface of the ramal shaft. Almost 

 complete disappearance of the coronoids has taken place. 



Almost the entire skull of this bird is highly pneumatic, and I have carefully 

 compared it with the specimen loaned me by the U. S. National Museum, and find 

 that they agree in all essential particulars. In the latter I find a mandible 38 cm. 

 long, Avhile the symphysis of the same only measures 4 mm. The superior carina- 

 tion of the united palatines is somewhat higher, especially in front than in my own 

 specimen, but I am inclined to believe that in mine the free margin has somewhat 

 broken off, and due allowance should be made for it in the figure illustrating the 

 skull of this bird in my earlier memoir (Fig. 40) showing the lateral view of the 

 Pelican's skull, when the supero-median palatal keel is drawn a little too low. 



Fig. 20 of Huxley's 1867 paper in the P. Z. S. is a good representation of the pos- 

 terior half of the skull of a pelican (P. onocrotalus) seen upon its basal aspect. The 

 side view of the same is very indifferently drawn. 



Some few of the small bones of the disarticulated National Museum specimen 

 at my hand may have been lost, but none of any consequence. Almost the entire 

 skeleton is pneumatic, and exceedingly light. The pygostyle is as light as a wafer, 

 and taken with all the caudal vertebne, only weighs a few grains. Among the non- 

 pneumatic bones we note the atlas, the fibulae, the first metatarsal, and all the toe- 

 joints. Some of the bones are actually riddled with air-holes, and such a long bone 

 as the humerus has many minute foramina at very various localities at both of its 

 extremities. The pelvis weighs no more than were it made of cork, and so it is with 

 all the other large bones. 



Of the Remainder of the Axial Skeleton in Pelecanus. 



(See Plate XXVII., Figs. 31-34, 38, 39; PI. XXVIIL, Fig. 42, and PI. XXX., 



Fig. 49.) 



Professor Mivart found in the spinal column of a specimen of Pelecanus mitratus in 

 the British Museum but "forty vertebne in all, there being but three lumbar and five 

 caudal" ; and in a specimen of P. onocrotalus (No. 527A), forty one vertebrse, there 



