34:8 Transactions. — Zoology. 



slender, simple, widely- arched furcula. Whilst, as Professor 

 Huxley^'- has shown, it is a special characteristic of this ral- 

 line genus for the coracoid and scapula to meet at an obtuse 

 angle. 



Almost unfitted for sustained flight, the wing-bones of 

 Oqjdromus are feeble in the extreme as compared wdth those 

 of the bird in question. The two could not for a moment be 

 mistaken for one another in size, relative stoutness, configura- 

 tion, bony prominences, and muscular impressions. 



The large pelvis in all its aspects agrees with that of the 

 fowl race. Very broad fore-iliac plates are continued back- 

 wards towards the acetabulum. The post-iliac or rump 

 region is still wdder, full, flattish, or smoothly convex, the 

 interior being uniformly capacious. The remarkably deep 

 ischia project beyond the outer border of the post-ilia. 

 The pubic rods reach ^in. behind the V -outlined ischia. 

 The iscliiatic foramina are large and antero-posteriorly oval. 

 There is a prominent cotyloid or prepubic process. The Ocy- 

 -dromine pelvis, on the contrary, is distinguished by its uncom- 

 mon narrowness and restricted capacity, being bottle-shaped, 

 or with unusually deflexed and laterally-compressed fore- 

 and mid-ilia. The rump-region is equally narrow, prominently 

 and obliquely ridged atop, and square-set behind : this by 

 reason of an overeaving of post-ilia over the small, straight- 

 set, impressed, vertical, and terminally-truncate ischia, which 

 the straight pubic bars barely pass. Prepubic processes mi- 

 nute ; sciatic foramina small and roundish. 



The specialized hind limbs of Ocjjdromus, so out of propor- 

 tion to its diminutive wing, would suggest some trace of such 

 difference in the bird supposed crossed from it. Such, 

 indeed, was not the case. The moot bird had, it is true, big 

 leg-bones, but these were quite in keeping with the dimen- 

 sions of its wing-elements, and not exaggerated relatively to 

 the latter, as is the ralline peculiarity. The leg- and toe- 

 bones strictly agreed with those of the fowl in every parti- 

 cular, bony processes and ridges being very pronounced, and 

 general stoutness considerable, as opposed to Ocydromus. In 

 the femur the trochanteric eminence, superficially and other- 

 wise, was great, the external condyle lower than the internal. 

 The tibial cnemial process was towards the median line and 

 lengthened, the inner distal tibial knuckle the largest ; the 

 fibula reached to the end of the shaft of the tibia. The bone 

 of the upper post-tarsal projection was short and perforated. 

 Hind-toe bones as long as the first phalanx of the mid-toe ; 



•«' Classification of Birds," P.Z.S., 1SG7, p. 425 ; and "Anatomy of 

 Vertebrated Animals," 1871, p. 289. An observation first made by Pro- 

 fessor Newton (see " Birds of New Zealand," 2nd ed., vol. ii., p. 108, foot- 

 note). 



