352 MR. R. S. -WRAY ON THE MORPHOLOGY [Apr. 5, 



t. medife, T.Md, but scantily represented on the manus. There is 

 part of a row, T.Mn, representing the minores, and a few rows of 

 marginals, M. The dorsal surface of the humerus is uniformly 

 covered by rows of feathers. The pollex bears four reaiiges and a 

 few coverts, Al. 



The disposition with regard to the bones gives 16 primaries or 

 metacarpo-digitals, and about 20 (20-22 or 23) cubitals. The quills 

 have not the same firm attachment as those of the Carinates, there 

 being no grooves in the phalanges to receive them, and their bases 

 project beyond the anterior edge of the bone (f/.fig. 2, p. 351). In the 

 Carinatse the quills attached to the phalanges lie almost parallel to 

 them, whereas here the angle is little larger than a right angle. This 

 is a much more primitive condition. 



The primaries are disposed as follows : — Eight metacarpals, one 

 addigital, four middigitals, and three predigitals. This probably 

 represents a more primitive wing-form than the Carinate, where 

 seven metacarpals and five digitals is the highest number of pri- 

 maries. Probably the ancestral wing-form became modified into 

 the forms we know by reduction and specialization of these feathers, 

 seen more numerous in the Ostrich than elsewhere. 



The Rhea's wing presents the same general characters as the 

 Ostrich ; the ventral surface is bare, and the dorsal surface, with the 

 feathers cut, shows the same arrangement ; but when the relations 

 of the remiges to the bones are considered, it is seen to approach 

 more nearly to the Carinate type in some respects. The primaries 

 are twelve in number, there being seven metacarpals, one addigital, 

 two middigitals, and two predigitals. This reduction is correlated 

 with shortening and reduction of the manus. The angle of insertion 

 of the digitals is more obtuse than in the Ostrich. 



The wing of the Emu I have not had the opportunity of dis- 

 secting, but it is probably similar in arrangement to the Ostrich and 

 Rhea, judging from a stuffed specimen. 



The wing of the Cassoway^ shows a great exaggeration of the 

 feature, noticed in the Ostrich, of the quills projecting beyond the 

 bones, its quill-spines being the sole remains of the cubital remiges. 



The Apteryx shows, as was first pointed out by Prof. Flower 

 (Roy. Instit. Lect. I88G), afew true cubital remiges, indicated by 

 their long quills. 



The PenguirCs Wing. 



This departs the most of all wings from the general plan. The 

 paddle form of the wing and its scale-like feathers are familiar, and 

 there is little or no differentiation apparent beyond the passage from 

 mere scales anteriorly to feathers posteriorly. On the ventral side 



^ In the wing of a Cassowary dissected since writing the above there are 

 to be seen structures representing, in all probability, the " primaries," which 

 appear at first sight to be entirely wanting in these ibrms. I hope to describe 

 this specimen, together with some other interesting Ratite wings, in a future 

 paper. 



