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are a femur, tibia, and fibula, and some cervical vertebræ of the same bird, dug up by my son from the menaccanite bed at the base of the inland cliff at Te Rangatapu; though belonging to a young individual, as is shown by the still incomplete union of the proximal epiphysis of the tibia, they are of gigantic proportions. The femur is fourteen inches long, and nine inches in circumference; the tibia, thirty inches in length, six inches round the shaft, and fourteen inches in circumference at the distal end. The entire skeleton of this bird was exposed on removing the soil; the skull and vertebræ of the neck lying extended, and the spinal column, pelvis, and bones of the hind limbs disposed in their natural relative position; but, owing to the sudden inroad of the natives, a few bones only could be rescued from destruction, and in the confusion that ensued, the identification of the bones of the same individual could not with certainty be determined. The femur, tibia and fibula, however, unquestionably belonged to the same bird.

As a guide to the scientific observer, or the student in palæontology, I will point out a few of the most striking peculiarities of the respective parts of the skeleton contained in this collection; but without reference to specific distinctions. It will be sufficient, for example, in reference to the tarso-metatarsal bone, to state that in the genus Dinornis it has three trochlear articulations; while in that of Palapteryx there is a posterior depression for the articulation with the metatarsal of the hind toe; the birds of this genus being tetradactyle, or four-toed, like the Apteryx.

Spinal Column.-Table-Case 17.-The bones composing the spinal column are characterized by their massive proportions, the remarkably thick quadrate spinous processes, especially of the cervical vertebræ, and the small size of the neural canal, indicating a very slender medullary chord. "We may associate with such a condition of the spinal marrow," Professor Owen remarks, "less delicate perception, and less energetic muscular action; thus the characters of the vertebræ confirm the original induction from the texture of the femur, that the Dinornis was a more sluggish bird than the Ostrich."1

1 Consult the commentary on the anatomical characters of the Dinornis, &c. in "Zool. Trans." vol. iii. p. 307, and p. 345.

Sternum.-Portions of several large sternal bones have been obtained. The most perfect example is that figured in Zool. Trans. Vol. iv. Pl. IV. It is of a shield-like form, entirely destitute of a keel, and very slightly convex: it is remarkable for its breadth; the anterior border from one costal angle to the other is seven inches; it has a broad median process, and two very long diverging lateral ones. As these characters resemble those of the Apteryx, this sternum is referred to Palapteryx rather than to Dinornis.'

Pelvis.-There are in the wall-cases portions of pelves of great size, and which in all probability are referable to the most colossal species of Dinornis or Palapteryx. In respect to this part of the skeleton the extinct birds approach nearer to the tridactyle Gralla than to the living Struthionida.

In the table-cases there are several delicate pelves of birds of small size, belonging to several genera; they are extremely fragile, and were broken to pieces during their long transport, and have been repaired with much trouble. Some of them belong to the genus Apteryx; apparently the existing species: others to the bustard-like bird, the Aptornis. There are many specimens of the coalesced pubis and ischium of different kinds of birds.

Femur or thigh-bone.-Table-Case 15.-The femur of the Dinornis is remarkable for its great strength. The trochanter is very broad, thick, and elevated; the distal extremity is of great size, and the rotular cavity very broad. The shaft is rounded, and the muscular ridges and tuberosities are more strongly developed than in any other birds. There is no aperture for the admission of air into the interior of the shaft of the bone; and both the weight and cancellous structure prove the accuracy of Prof. Owen's original statement in his description of Mr. Rule's fragment of the shaft, that the Dinornis at all ages retained the medullary contents of the cavities of the femur, as in the Apteryx; the only other example of a terrestrial bird in which the air is not admitted into any of the bones of the extremities.

The absence of the pneumatic foramen and canal, the great thickness of the dense osseous wall of the medullary cavity of the shaft, the great size of the distal end of the bone, and the

1 See "Zool. Trans." vol. iv. p. 17.

breadth of the rotular cavity, are the chief generic characters of the femur of the Dinornis.' The largest femur is sixteen inches long, and the shaft seven inches and a half in circumference.

Tibia and Fibula.-Table-Case 15.-The Tibia, even in the species in which it is of great length, is relatively thicker and stronger than in the Ostrich or Cassowary. It is distinguished from the corresponding bone in the Struthionidæ by an oblique bony process that extends across above the distal trochlea, on the anterior and inner side of the bone, and forms a canal for the extensor tendon, as in the Bustard. The longest specimen of a tibia is nearly three feet in length, and the circumference of the middle of the shaft is six inches and a half. The tibia is strongly marked by a ridge for articulation with the fibula, which is a long and very slender bone extending two-thirds down the shaft of the leg-bone, and entirely free. My son collected several very large fibula belonging to Dinornis and Palapteryx; and many that are referable to other and much smaller birds. It is remarkable that such delicate fossil bones (as those in the table-cases) should have arrived from the Antipodes in so perfect a state.

Tarso-metatarsals.—Table-Cases 15, 16, 17.—The tarsometatarsal (shank-bone) is so named because it is formed by the coalescence of the tarsus and the three primary metatarsals into a single bone, which at the distal end is divided into three trochlear articulations for the corresponding number of toes. In the Dinornis this bone is remarkably strong and broad, and of great width at the distal or trochlear extremity. The proximal end has two concavities, the inner one the deepest, for articulation with the tibia. There are no indications of a posterior toe: the Dinornis being a tridactyle, or three-toed bird.

In the unique specimens of the entire series of bones of both feet with the two metatarsals of the same individual of Dinornis robustus, collected by my son at Waikouaiti, there is not the slightest trace of an articulating surface for a hind toe.

The ossification of the metatarsals in the Dinornis appears not to have been perfected till a late period, as in the existing

'See" Zool. Trans." vol. iii. p. 248.

struthious birds; for in the specimens alluded to, the division of the original three metatarsals is strongly marked, and one of the bones has, unfortunately, cracked by drying, along the line of separation of the primitive ossicles; and yet these bones appear to have belonged to a mature individual.

The longest tarso-metatarsal bones I have seen are eighteen inches and a half in length, the circumference of the shaft being five inches and a half.1

Phalangeal Bones.-The bones of the feet bear a closer resemblance to those of the largest species of Apteryx, Ap. Australis, than to any of the other existing struthious birds. The phalanges present the ordinary numerical progressive increase, viz. the inner toe is composed of three bones, the middle of four, and the outer of five. The proximal articular surface of the first phalangeal of the middle toe is symmetrically divided by a slight ridge, as in the Cassowary; but in the inner and outer toes the corresponding bone has the proximal end deeply notched, and the inner half greatly produced to embrace the corresponding trochlear surface of the metatarsal.2 The ungueal or claw-bones are large and strong, of a subtrihedral form, and gently arched.

In his last visit to Waikouaiti, my son dug up the entire series of phalangeals with the corresponding metatarsal of a smaller species of Dinornis; but whether referable to D. dromioides or D. rheides, or to a distinct species, is uncertain, for the metatarsal corresponds with that assigned to the former in Zool. Trans. vol. iv. Plate III. fig. 1, while the series of phalangeals are unquestionably of the same species as those figured in Pl. II., and ascribed to D. dromioides.3 In the reconstruction of the foot of the Dinornis robustus, my son's specimens have afforded a certain guide.

Several phalangeals were discovered, in which the trochlear articulation of the proximal bone of the middle toe is as unequally divided as in the Ostrich ; a character which seems to indicate that a didactyle, or two-toed wingless bird, may have

1 These specimens are figured as the frontispiece of the "Pictorial Atlas of Organic Remains."

2 See figs. 1 & 3 of the same plate.

3 As the restoration of these parts is based on detached specimens, it is probable the metatarsal does not belong to the series of phalanges with which it is associated.

inhabited New Zealand contemporaneously with the tridactyle Dinornis, and tetradactyle Palapteryx, Aptornis, and Apteryx,

Foot of Dinornis.-The structure of the locomotive organs of one of the largest of the extinct ostrich-like birds is demonstrated by the entire series of bones of both feet of the same individual discovered at Waikouaiti: the dimensions of the several elements are given in the Appendix.' Allowing the usual proportion of the soft parts and integuments, the length of the foot in the living bird may be estimated at about sixteen inches, and its breadth at eighteen inches.

According to the relative proportions of the bones composing the hinder extremities of the gigantic species of Dinornis, the height of the bird to which these feet belonged was probably nine and a half or ten feet.

From the great width and solidity of the metatarsals, and the form and corresponding size and strength of the phalangeals and ungueals, it is certain that the feet of the Dinornis must have constituted powerful instruments for scratching, digging, and uprooting subterrestrial vegetable substances, which, from the structure of the crania and beaks, have with much probability been supposed to have constituted the principal sustenance of the original.

Bones of the thigh, leg, and feet, of larger proportions than those above described, are in the Wall-case C, and in my own collection. Some of these indicate birds of eleven or even twelve feet high; dimensions exceeding by one-third the stature of the tallest Ostrich while in other species, as Dinornis struthioides, D. dromioides, D. curtus, and D. didiformis, the stature is respectively seven, five, and four feet.

Palapteryx.-Wall-Case C.; Table-Case 16. Lign. 28, 29. -The other generic type, which comprises some of the largest species of the extinct birds, has been named Palapteryx; but it is not, as the term would seem to imply, so nearly related to the existing wingless bird of New Zealand, the Apteryx, as to the Dromaius or Emeu.

Of this genus there is a nearly entire cranium, with the upper and lower mandibles, and several imperfect skulls and beaks,

1 Appendix D. Dimensions of the bones of the foot of Dinornis robustus. See also" Quarterly Journal of the Geological Society," vol. vi. p. 338.

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