338 



MR. W. K. PARKER ON THE OSTEOLOGY OF BAL^NICEPS REX. 



coracoid for the thick part of the furculum, which does not exist in the Adjutant. The 

 coracoid of the Balaeniceps (Pi. LXVI. fig. 1, and PL LXVII. fig. 1 cor) is half an inch 



Balfeniceps. 



Adjutant. 



Grey Heron. 



Length of scapula 



Greatest breadth of scapula {flat part) 



Greatest length of coracoid 



Breadth of lower articular surface of coracoid 



Length of sternal keel from apex to end 



Breadth of sternum across costal processes 



Breadth of sternum across hyposternals 



Length of hyposternal processes 



Thickness of keel at the margin near the furculum. . 

 Greatest depth of keel 



inches, lines. 

 4 3 



10 

 5 

 

 



61 

 4 

 4 

 3 



inches, lines. 

 5 C 

 8 

 9 

 1 

 7 

 2 



lOi 

 8 

 Ja 

 



inches, lines. 

 3 2 

 2 



2 7 



3 6 



1 lOi 



I C 



8 



1 



1 



broad at the middle part, and five lines thick ; it then expands, is deeply grooved in 

 front, has its internal edge sharp, which sharp edge at the top forms that incurved flat 

 process which articulates by ligament with the tip of the ramus of the furculum, and 

 with a similar but thicker process at the upper part of the proximal end of the scapula. 

 The shallow glenoid cavity belongs equally to the scapula and the coracoid. 



The sternum of Balaeniceps (PI. LXVI. fig. 1 st, and PL LXVIL fig. I) differs from 

 that of the Heron and agrees with that of the Adjutant in being very thick and cellular, 

 except at its hinder part. Notwithstanding the thinness and delicacy of the sternums 

 in the genera Ardea, Botaurus, Nycticorax (Nycterodius, Macg.) and Cancroma, they 

 agree in all essentials with those of the true Storks. In Balaeniceps, however, we 

 encounter a host of difficulties both in the sternum and also in the furculum 

 (PL LXVI. fig. 1/c, and PL LXVII. fig. 1 sy), although its general shape and proportions 

 agree well with that of the gigantic Storks. The hyo-sternals, or costal processes, are 

 exactly like those of the Adjutant, but the epi-sternal process, which is distinct in the 

 Adjutant, and long in the typical Herons, is not differentiated in Balaeniceps. In 

 Parrots, Woodpeckers, and Horn-bills, that emargination is absent which separates 

 the epi-sternum in most birds from the tip of the sternal keel. The same thing occurs 

 in the Balaeniceps ; so that in this Wader, as well as in those arboreal birds, the keel of 

 the sternum projects some distance in front of the coracoid grooves. In all the more 

 delicately formed Ardeine birds that we have examined, there is an ascending process 

 within the angle and between the rami of the furculum ; this is absent in Balaeniceps, 

 although it is present in Cancroma. In the latter bird, in the Bittern {Botaurus stellaris), 

 and the Purple Heron {Ardea purpurea), the furculum is connected by ligament to the 

 tip of the sternal keel ; a state of things which occurs in the great majority of birds. 



In Ardea cinerea (and most of the larger Herons), in Nycticorax griseus, Botaurus 

 minutus, and in the genera Ciconia and Mycteria, the end of the furculum has a gliding 

 synovial joint with the tip of the keel of the sternum ; and this appears to be persistent 



