* 
25 
In 1863 I had the opportunity of making known to the Bishop of Mauritius the 
desirability of obtaining for the British Museum any remains of the Dodo which, 
through his Lordship’s recommendation and influence, might be discovered in that part 
of his diocese; and in 1865 I received from Mr. George Clark, Master of the Diocesan 
School at Mahéburg, Mauritius, the series of bones which formed the subject of a paper 
on Didus ineptus published in the sixth volume of the ‘Transactions of the Zoological 
Society of London.’! 
Accessions of bony remains speedily followed, both from the Mauritius and the 
neighbouring island of Rodriguez, the latter throwing the same light upon the extinct 
“Solitaire” of the old French voyager Leguat as the Mauritian remains had done on the 
““ Walgh-vogel,” “ Dronte,” or ** Dod-aers” of the contemporary Dutch seamen. 
The osteology of the Solitaire, referred to a genus Pezophaps by Strickland, forms the 
subject of an instructive paper in the ‘ Philosophical Transactions’ ’. 
I propose in the present ‘Supplement ’to combine observations on the skeleton of 
Didus ineptus, L., with those on Didus solitarius, Gm. (Pezophaps, Str.). 
Both extinct birds agree in the extent and kind of anchylosis in the dorsal region of 
the spine: it affects the three vertebre preceding the last free, rib-bearing dorsal. In 
both species the neural spines have run together into a bony ridge, with a straight, 
thickened upper free border. In both the confluence of the neural arches is only 
interrupted by the conjugational foramina, which are similar in size and shape. 
My series of these coalesced vertebra included two varieties:—one showing a feeble 
beginning of the hypapophysis at the fore part of the last vertebra (pl. 17. fig. 5, O.); 
the other a better-developed, though small, hypapophysis, but so extended as to reach, 
and coalesce at its extremity with, that of the antecedent vertebra, leaving a vacuity 
corresponding with the wider one between the first and second of the coalesced hyp- 
apophyses. In Pezophaps the specimen (pl. 15. fig. 51, N.) resembles the variety (pl. 17. 
fig. 5, O.) of Didus, save in the absence of any indication of hypapophysis on the third 
vertebra, And in the instructive example of the three partially anchylosed vertebre of 
a young Pezophaps (pl. 16. fig. 60, N.) the third vertebra shows no hypapophysis*. In 
this specimen anchylosis is seen to have begun at the neural arch and spine, chiefly be- 
tween the first and second vertebrie, and co-ossification of the centrums is more advanced 
between the first and second than between the second and third of these vertebrae. 
The inference that these anchylosed vertebra included the penultimate, antepenulti- 
mate, and the next dorsal vertebra in advance, and that only one free dorsal vertebra 
! Communicated January 9th, 1866 (p. 49). | 
® By Professor A. and Mr. E. Newton, “On the Osteology of the Solitaire, d&c.,” Phil. Trans, 1869, pls. 17 & 18, 
figs. 66, 68-70. Future references to this interesting and instructive Memoir will be made under the 
letter N.; those to my own Memoir, of 1866, on Didus by the letter O. 
* In other respects the last of the three anchylosed dorsal vertebrae in Pezophaps does “ bear a great general 
resemblance to the same bone in Didus.” 
F 
ii a a 


