236 



THE EXTINCT BATRACHIA, REPT1LIA 



Class III.- A. V E S . 



T O T I I* ALMA T I . 



SULA, Briaaon. 



SULA L0X08TYLA, Cope. 

 Spec, nov. (ig. 5:>. 



This species is established on a single coracoid bone which I found at the Coot of the Miocene cliffs in Calvert (Jo., 

 Maryland. The furcular articular surface is broken off, as well us the exterior half of the posterior or sternal articu- 

 lar extremity. The extremity of the scapular surface is also Injured. Sufficient of the bone; remains to furnish many 

 characteristic peculiarities, and indicate its affinity to the totipalmate family of the Gannetts or Sulide. 



The bone is stout, and Indicates a bird of strong Sight. The shaft proper is rather short, and sub-oylindrio, with 

 a trihedral tendency. This form, with the expanded distal extremity, indicates its wide distinction from the cora- 

 coid of the GaUinacete. Its sub-cylindric shaft marks considerable difference from the Lamellirostres and many other 

 aquatic types. Its lack of inner subclavicular ala, and foramen, distinguishes the type from Raptores, the majority of 

 Fig. 5:). Longipennes and many Grail®. The presence of a, marginal groove or rabbett, distinguishes 



it not only from most Psittaci and Insessors, but from many Natatores also. After a study of 

 the large collection of bird skeletons in the Museum of the Academy Natural Sciences, aided by 

 the Oissaux Fossiles of A. Milne Edwards, I find It resembles closely the genus Bula. 



The glenoid articular face descends to opposite the proximal third of the length; it is trans- 

 versely concave, and its inferior boundary is raised to separate, it from the longitudinal concavity 

 which extends to the head of the bone. A longitudinal angle separates this from the interior 

 part of the inferior face. The anterior extremity is curved upwards and is thinned by a, strong 

 rabbett, which follows the convex margin. This margin is slightly obtuse. The outline is 

 abrubtly contracted below the glenoid surface. The inner outline is obtuse, and Without trace 



of the intermuscular ridge, on subclavicular ala. The margin expands inwards to the distal 

 articular extremity, remaining almost equally obtuse. The distal extremity is far lews expanded 

 towards the median lint! of the sternum than in Sula bassana. if is also everted, the outer 

 (inferior) projecting border, being turned out (down) from the line of the shaft. In Sula, has 



sana, this marginal rim appears, from Edwards' plate, to be in the plane of the shaft. The articular sur- 

 face is divided by this rim int.. a, narrow marginal external (inferior) and a very much wider, strongly concave Inner 

 portion. The latter is wider at the median end, when; its inner (superior) margin is very convex; it then contracts 

 abruptly, leaving the remaining portion only one-half as wide. The very slight prominence of the dividing angulate 

 projecting margin, distinguishes this genus from Sula, bassana,. 



There are three pneumatic foramina of no great size, in a, short series commencing just within the head of the 

 bone. 1 am only able to compare this bone with the figure of the same elementof the Sula bassana given by Edwards, 



as our museum does not possess a skeleton referable to this genus. 



As compared with the above, the glenoid articular face descends more posteriorly (lower), and the superior 

 (proximal) margin is more transverse. The shaft, viewed from before (below), contracts gradually towards the distal 



expansion. The same contraction is visible when viewed from the inner side. On the same view we observe; that (he 

 clavicular articulation is rather mpre posterior (lower down), and the distal articular marginal edge is far less promi- 

 nent and acute. The inferior (outer) narrow articular margin is much narrower than in S. btixmna. 



Inches. 



2.02 



.78 

 .57 

 .25 

 .2:! 



Length to Inner distal angle, 



" " posterior basis of scapular articulation, 

 \\ idth of l»ead last point, 



" " glenoid cavity, 



" . " shaft, 



" " disial extremity to middle line of shaft produced, 



Thickness disial extremity, 



Mi 

 .88 



