Zoological Affinities of Aphanapteryx. 269 



them is of somewhat great breadth ; there are no pits below for 

 lodging the posterior edge of the glenoid facets of the metatarsus, 

 in the way that is seen in many of the Waders. The furrow of 

 the anterior tibial muscle passes under a well-developed bony 

 point ; the groove of the short peronean muscle is hardly in- 

 dicated. 



Among the Rails, Ocydromus alone offers like peculiarities in 

 the structure of the leg-bone ; and there they differ remarkably 

 from the other genera of the same family ; for in them the tibia 

 is relatively much more elongated, the articular extremities are 

 more in proportion to the size of the diaphysis and the tibial 

 ridges, and much higher and more prominent. In this respect 

 there are many more differences between the structure of the 

 normal Rallidce and of Ocydromus than exist between this last 

 and our fossil. Indeed it is to be remarked that the tibia of 

 Ocydromus is comparatively very thick and short, and that its 

 extremities, particularly the upper one, are more swollen than 

 is usual, without, however, being nearly so much so as in our 

 fossil. The osteological peculiarities of the lower extremity are 

 the same, but the diaphysis in Ocydromus is less bowed. The 

 tibia of Apteryx differs much from that of the Mauritian bird : 

 the direction of the tarsal articulation is quite otherwise; the 

 relative size of the condyle is not the same ; the furrow of the 

 anterior tibial muscle does not pass under a bony bridge, and 

 remains uncovered ; the anterior tibial ridge is much less pro- 

 minent, and so forth. There is, however, in the general aspect 

 and the relative proportions of the bone, something which recalls 

 those of the fossil, indicating that, though belonging to a bird 

 of a distinct zoological group, it presents some traces of resem- 

 blance to this singular genus of the Brevipennate group. 



The proportion in the length of the bone of the foot and of 

 the leg is not the same as in Ocydromus or Apteryx — the tarso- 

 metatarsus being notably longer, and being equal to two-thirds 

 the length of the tibia. Thus, if the dimensions of the last 

 bone are represented by 100, the length of the tarso-metatarsus 

 would be 67, while in Ocydromus it would be only 57"5, and in 

 Apteryx 54. 



Elsewhere in the family Rallidce these projjortions vuiy 



