450 • Zoological Society : — 



the angle, where it makes a most complete anchylosis with the tip of 

 the sternal keel. This structure of the furculum is similar to what 

 is found in Pelecanus, Phalacrocorax, and Sula ; hut we have seen 

 no such " merry-thought " bone in any Ardeine hird. In these, as in 

 Bal(Bnicej)s, the rami of the bone are not only flat as they pass in 

 between the heads of the coracoids, but this thin condition of the 

 bone is continued throughout one-half of their extent. They have 

 no such sudden bend at the upper third, the arch being gentle, and 

 the lessening size of the bone gradual. Nevertheless, in the Boatbill 

 there is a slight tendency to this state of things. The blending of 

 the furculum with the sternal keel seldom takes place in the true 

 Herons and Storks; there continues even in old birds a synovial 

 gliding joint, and in the Boatbill and some of the smaller Herons the 

 furculum does not quite reach the sternum. This articulated con- 

 dition is generally found in Gannets and Cormorants ; but in old Pe- 

 licans anchylosis of the joints takes place. This occurs too in the 

 Secretary bird, which is unique among the birds of prey in having 

 a joint there at all, so that this last-mentioned bird is a raptorial 

 isomorph of the Cranes. In the latter birds (the Griiidce) there is 

 great difference in the structure of these parts ; for whilst in such 

 species as Grus Antic/one and G. americana we have in the adult 

 bird complete coalescence, in the Balearic Crane, G. 2)avonina, and 

 in the Trumpeter, Psophia (a Crane becoming slightly gallinaceous), 

 the furculum does not reach the sternum at all. 



Any lengthy remarks upon the bones of the limbs need not be 

 made at present. They are about three-fourths the size of those of 

 the Adjutant ; but as the limbs had not enjoyed much liberty of 

 exercise, they have not that robustness which is seen in the skeleton 

 of old wild birds. The humerus is longer relatively, and the fore- 

 arm shorter in proportion than in the Adjutant ; the thigh-bone is 

 longer in proportion to the tibia and tarso-metatarsus in the Balceni- 

 ceps than in its larger relation. The toes are very long, reminding 

 one of those of the Japanas (Parra) ; and the most ridiculous care 

 which this stilted, stalking bird takes, both in taking up and setting 

 down its feet, makes it worth while to compare the length of the bones 

 of its toes with that of the bones of the toes of the Great Adjutant. 



Hallux. Inner toe. Middle toe. Outer toe. 

 in. in. in. in. 



Adjutant 2-3 4*15 57 A- 7 



Baheniceps 3'3 3'8 6*5 6*4 



To conclude, I may remark that upon a careful examination of the 

 osteology of the Balceniceps, after eliminating the teleological from 

 the relational characters, I am decidedly of opinion that it is strictly 

 an Ardeine bird, and more nearly related to Cancroma than to any 

 other known type. 



Note I. — Amongst the bones of the limbs, the humerus alone is 

 pneumatic, — the cavity of the os femoris being filled with medulla, 

 as are all the more distal bones. 



Note II. — The tongue is extremely small — an important Pelecanine 

 character. 



