688 DR. p. CHALMERS MITCHELL ON THE 



Clearly, so far as the evidence from muscular anatomy goes, 

 Balceniceps is an ally of Scojyns, Herons and Storks, and shares 

 many characters with these birds and Steganopods. The two 

 facts that impress me most are the close similarity of the rather 

 highly specialized patagial muscle and tendons in the case of 

 Balceniceps and Scopics, and the very remarkable condition of the 

 pectoralis thoracicus found in Balceniceps and Storks, but which 

 probably also exists in Scopus, and certainly in Peleccmvs and 

 some other Steganopods. 



OSTEOLOGICAL NoTES. 



As the osteology of Balceniceps has been described at length 

 in W. K. Parker's well-known monograph (33), and as I have 

 not the time at my disposal to make the elaboi^ate study of 

 the different types of Storks and of Herons which is necessary 

 before final conclusions can be drawn from the skeleton of 

 Bcdceniceps, I must content myself with a few notes on some of 

 the salient points which struck me as requiring special study. 



Occipital condyle. — ^In Balceniceps this, seen from in front and 

 below, has much the appearance of a moderately dolicocephalic 

 human cranium. It is sessile, elongated antero-posteriorly, and 

 its posterior margin, where it projects slightly into the foramen 

 magnibm, is convex. In the Herons the condyle is transversely 

 elongated, and the posterior margin, where it projects into the 

 foramen magmmiy is the broadest part, is concave and slightly 

 grooved, as if to form the beginning of two condyles. In Scopus 

 the condyle is also transversely elongated but not so much as in 

 Herons, and its foraminal margin is abruptly truncated. In 

 Anctstoinus, Dissura, Xenorhynchus, and Giconia the long axis is 

 transverse, and the foraminal mai'gin is concave or notched. In 

 T'antcdus, on the other hand, the condyle is nearly spherical, and 

 although a notch may just be indicated, the foraminal mai-gin is 

 convex. The configuration of the condyle in Bcckvniceps is, there- 

 fore, unlike Scopus, Storks or Herons, but it is most nearly 

 approached by the Tcmitalas Storks. 



Faroccipitcd processes. — The bi'oad, thin and shell-like pro- 

 cesses which bend down over the articulation of the quadrate 

 ai-e repeated on a smaller scale in Tantalus, where however the 

 laminae are relatively thicker and less extensive. In other Storks 

 they are replaced by similarly situated, thick and curving ridges. 

 In Scopus and Herons all a.ppearance of the shell-like arrange- 

 ment is absent. 



Basitempoird plccte. — In Bcdcenicep>s the anterior margin of this 

 has a crescentic free edge which nearly meets at each side a curved 

 lamina projecting from the basisphenoid, so that the Eustachian 

 tubes are nearly floored in below. Parker wrote that " in the 

 Heron these parts are essentially a miniature" of those in Bcdce- 

 niceps, adding that this " is certainly not a faint and superficial 

 mark of aftinity." But the similarity extends to Scopus and 



