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otidiformis. Now, this orifice is not present in one of three metatarsi of Apt. otidi- 
formis, nor in one of the two metatarsi of Apt. defossor. Neither the vertical nor the 
fore-and-aft canals are present in Dinornis: I have once seen the latter canal, as an 
exception, in Apterya. 
At the back part of the shaft Aptornis defossor shows a perforate calcaneal process 
(Pl. LXX XVII. figs. 2, 3, ¢), relatively longer vertically than in Apt. otidiformis: the 
ridge on the inner side of each side-wall (fig. 4), indicating the portions of the canal tra- 
versed respectively by the tibialis posticus (¢’) and the “ flexor longus digitorum ” (@), is 
better marked, and the bony canal is less contracted posteriorly, than in Apt. otidiformis. 
The postinternal longitudinal crest is shorter and more produced in 4pt. defossor; the 
fossa internal to its upper part, for the origin of the “flexor brevis hallucis,” is well 
defined, as is the surface below the crest for the attachment of the metatarsal of the 
hallux (fig. 2,1). ‘The longer surface at the outer and back part of the metatarsal for 
the insertion of part of the strong gastrocnemial sheath-like tendon is strongly marked. 
Every thing bespeaks the force with which this massiye metatarsal was worked in 
Aptornis. ‘The proportions and disposition of the distal trochlee in Apt, otidiformis 
(fig. 5) are closely repeated in the larger species (fig. 1,@); the inner one (fig. 2, 11) 
does not terminate at a higher level than the outer one (ib. 1y); the cleft between the 
outer and middle trochlee is deeper and anteriorly wider than the inner cleft, in both 
species of Aptornis. The outer trochlea in Dinornis (fig. 8, 1v) is shorter than the inner 
one (ib. 1). 
To exemplify the generic, or family, or ordinal distinction between dptornis and 
Dinornis, L take the present opportunity to figure the metatarsus of the species coming 
nearest to Aptornis in size’, viz. D. curtus (Pl. LX XXVIII, figs. 7-10), first indicated by 
the mutilated bone described and figured in Pl. XX XIX. fig. 6. 
The metatarsus of 4ptornis defossor, above described, formed part of the extensive 
series of remains brought by Mr. Walter Mantell from Ruamoa, Middle Island of New 
Zealand, and purchased by the British Museum in 1856 (pp. 223, 234), Deeming, 
then, that it might prove to belong to a larger variety of the Aptornis otidifornus of 
the North Island, I concluded to wait for further evidence, which the bones brought 
from the same neighbourhood (Oamaru) by Mr, Taylor have now given, ‘The tibia 
(Pl. LXAXXTYV, fig. 9) fits this metatarsus (Pl. LX XXVIL. fig. 1) as well as the tibia of 
Apt. otidiformis (Pl. XXY. fig. 5) fits the metatarsus figured in Pl. L. fig. 5. 
On comparing the metatarsus of dptornis with that of Notornis, Ocydromus, or 
Tribonyx, the bone* would seem, at first sight, to drive the extinct genus far away from 
the Ralline waders: the occiput of Aptornis hardly presents more marked differences 
from that in any known recent Ralline’s skull. 
* Unless the small bone (Pl, LXXXTY, fig. 7) should indicate an established breed of that inferior size, 
meriting a distinctive name, and should not belong to a female or somewhat dwarfed individual of D. curtus. 
* Pl. L, figs. 5-8; and Pl, LXXXVIL, figs, 1-6, 
