PECTORAL AND PELVIC ARCHES OF ARCH JEO PTE R Y X . 



3 



irregularities in the rest of the border are probably clue to 

 imperfections in the fossil. 



As remarked by Huxley (1868), the furcula, {PL I. fig. 2) is 

 exposed from its ventral face. The new preparation of the 

 specimen has only defined more clearly the shape of the upper 

 articular end on the left side *. 



Table of Measurements. 



Scapula : mm. 



Greatest length to apex of acromion 46 



Greatest breadth of distal end 6 



„ „ proximal end 11 



Smallest breadth 3 



Greatest diameter of scapular part of glenoid fossa 5 



CORACOIB : 



Greatest length from prominence above glenoid fossa to 



infero-internal angle _.. 10 



Breadth at upper (humeral) border 9 



Breadth at middle 12 



Breadth at lower (sternal) border 12 



Greatest diameter of coracoidal part of glenoid fossa 3 



FURCULA : 



Greatest length 21 



Greatest width : 31"5 



Greatest breadth of bone 4 



Inner angle of furcula abGut 90°. 



It would be interesting to compare the pectoral arch of 

 ArcluEopteryte, as now made known, with the corresponding parts 

 in the second specimen in Berlin ; but, unfortunately, according 

 to the description by Dames (1897), the several bones in the 

 latter fossil are so imperfect, crushed, and obscured that no 

 .satisfactory comparison is possible f.. It must suffice to note that, 

 although Archctiopteryx was obviously a bird of flight, its scapulo- 

 coracoid is more closely similar to that of certain Mesozoic 

 reptiles than that of any other known bird, and the nearest 

 approach in shape to its coracoid is found in the existing Ratites 

 and the Cretaceous Hesperomis. In the fusion of the scapula 

 with the eoracoid and the very wide angle at which these bones 

 meet, it agrees only with the ratite birds and the reptiles. 



Pelvic Arch. 



In the pelvic arch (PL I. fig. 3) the right ilium (iL) and 

 ischium (is.) are exposed on their outer face, while the two 

 pubes (2 m -) are displaced and seen from above. The bones were 



' A small prominence on the stone below the middle of the furcula may perhaps 

 'mark the anterior end of the sternum (PI. 1. fig. 2. s.). — B. P. 



f I venture, however, to make the comparison, ^notwithstanding imperfections hi 

 tli!' Berlin specimen. — 13. l\ 



I* 



