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IX. On DiNORNis (Part IX.) : containing a Description of the Skull, Atlas, and Scapulo- 

 coracoid Bone of the Dinornis robustus, Owen. By Professor Owen, F.R.S., 

 F.Z.S., ^c. 



Read December 13, 1864. 



[Plates LIII.-LVL] 



§ 1. Skull o/ Dinornis robustus, /rom ' Timaru', Middle Island, New Zealand. 



1 HAVE been favoured by the kindness of Dr. D. S. Price, of the Crystal Palace, 

 Sydenham, with the opportunity of inspecting a series of bones from the Middle Island 

 of New Zealand, which were obtained under the following circumstances. 



" They were found at the bottom of a pit or crevice, about 50 feet deep, in limestone 

 rock, the upper opening of which was scarcely large enough to admit the body of a 

 man, but gradually widening as it descended, measuring at the bottom 30 feet by 4 feet. 

 The opening is on the top of a broken ridge of limestone rock, situated a few miles 

 south of ' Timaru.' There are many such holes in the immediate vicinity, in all of 

 which we found bones.'" 



From this series I have selected for the present description a mutilated cranium and 



lower jaw of a species of Dinornis, which, by its superiority of size over that of " a large 



kind " described in a former Memoir^, confirms the accuracy of the reference of that 



species to the Dinornis ingens, and leads me to refer the present specimen to the 



Dinornis robustus. The following are a few comparative admeasurements of the two 



crania : — 



Dinornis ingens. D. robustus. 



in. lines. in. lines. 



Breadth of cranium across the mastoids 3 H 4 



Length of cranium from superoccipital crest to premaxillary fossa 2 9 3 7 



Breadth, greatest, of premaxillary 2 4 2 10 



Breadth of cranium across the temporal fossae 2 8 2 8 



From these dimensions it will be seen that the present cranium, referred to D. robustus, 

 differs not only in size but in proportions from that of D. ingens, the breadth across the 

 temporal fossae being the same in both. This difference arises from the greater relative 

 depth of the fossae in D. robustus, indicating more power in the temporal muscles, and 

 is associated with mandibles which are more massive and broader in proportion to their 

 length. These and other differences will be readily appreciated by comparing figs. 1 & 2 



' Extract of a letter addressed to me by Dr. David S. Price, dated " Crystal Palace, Sydenham, August 20th, 

 1863." 



= "On Dinornis" (Part v.), Trans. Zool. Soc. vol. iv. p. 59, pi. 23. 

 VOL. V. — PART V. /^ 2 Y 



