Part 45

Habitat: Rodriguez Island.

2 Humeri, 2 Femora, 2 Tibiae, and 2 Metatarsi in the Tring Museum. {114}

ARDEA DUBOISI NOM. NOV.

Butors ou Grands Gauziers Dubois, Les Voyages faits par le Sieur D.B. (1674) p. 169.

L'Abbé Dubois is the only author who has, as far as I can ascertain, told us that the Island of Réunion also had a large almost flightless Heron as well as Mauritius and Rodriguez; and so feeling sure that it, like most other birds of this island, was distinct I name it after him.

The translation of his original description is as follows:--"Bitterns or Great Egrets, large as capons, but very fat and good. They have grey plumage, each feather spotted with white, the neck and beak like a Heron, and the feet green, made like the feet of Poullets d'Inde (Porphyrio, W.R.). This bird lives on fish."

Habitat: Réunion or Bourbon. {115}

ARDEA MAURITIANA (NEWT. & GAD.)

Butorides mauritianus Newton & Gadow, Trans. Zool. Soc. vol. XIII, p. 289 (1893).

The bones on which this species is founded are a pair of ulnae, one radius, four metatarsi, and one coracoid. The description is as follows:--"The bones in question are all considerably shorter than the corresponding bones of A. (Nycticorax) megacephala. The metatarsi agree otherwise in every detail with those of the latter species; this relative stoutness indicates that they belonged to a Night-Heron or Bittern like A. megacephala. The two ulnae cannot, unfortunately, be compared with those of A. megacephala; their length, 110 mm., compared with the length of the humerus of A. megacephala, 119 mm., shows, however, likewise that they were those of a considerably smaller bird. The single left coracoid agrees in all the features of its dorsal or scapular half with A. megacephala, but its ventral or sternal half differs considerably, first by the much more strongly marked ridge of the linea intermuscularis on its ventral surface, secondly by the almost straight instead of inwardly curved margin between the processus lateralis and the lateral distal corner of the sternal articulation, thirdly by a very low but very distinct and sharp ridge, which arises from the median margin of the coracoid, a little above its median articulating corner. This roughness or prominent ridge is entirely absent in A. megacephala and in all other Herons which we have been able to examine, but at least a slight indication of it occurs in an individually varying degree in Nycticorax and Botaurus. That this coracoid bone belonged, however, to an Ardeine bird is clearly indicated by its whole configuration, notably by the shape and position of the precoracoid process, the various articulating facets at the dorsal end, and the prominent lip on the visceral or internal surface of the median portion of the sternal articulating facet."

The following are the measurements:--

Length of ulna 111-112 mm. Length of metatarsus 81- 87 " Length of coracoid 48 "

Habitat: Mauritius.

Although megacephala and mauritiana have been placed in Ardea and Butorides respectively, from the short, stout legs and general build, I am inclined to think that all three of these Herons belong to the genus Nycticorax.

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PROSOBONIA BP.

This genus is, in the Catalogue of Birds, placed in a section with somewhat long tarsus, the latter being longer than the culmen, containing in addition to Prosobonia the genera Tringites, and Aechmorhynchus (see afterwards), and it differs from the latter by its long hind toe, from the former by its square tail. The position of this singular bird is, however, not quite certain. The late Henry Seebohm placed it in the genus Phegornis, though the latter has no hind toe whatever, and it has even--but doubtless wrongly--been suggested that it belonged to the Rallidae, rather than to the Charadriidae. We know only one species. It is true that Dr. Sharpe bestowed a new name on the figure of Ellis, which is said to have been taken from an Eimeo-specimen, but it is hardly creditable that it belongs to a different species. Latham appears to have had three specimens, which were all three different from each other. Both Forster and Ellis, in their unpublished drawings in the British Museum, as well as Latham, evidently considered all three to belong to the same species, and it is not advisable now to over-rule their verdict, given with the specimens before them, merely on account of the different plumages, since we all know that most waders, and especially brightly-coloured ones, differ considerably in plumage, according to age and seasons. We are convinced that "P. ellisi" has been a younger bird. Sharpe attaches importance to the different habitat, but this is no argument in this instance, because Eimeo is, at the nearest point, not more than seven and a half miles from Tahiti, and it is quite against all precedents among Charadriidae and beyond all plausibility that two such closely situated islands have closely allied forms of a Wader.

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PROSOBONIA LEUCOPTERA (GM.)

(PLATE 35.)

White-winged Sandpiper Latham, Gen. Syn. III, pt. 1, p. 172, pl. LXXXII (1785--Otaheite and Eimeo).

Tringa leucoptera Gmelin, Syst. Nat. I, p. 678 (1788--ex Latham!); Westermann, Bijdr. Dierk. I, p. 51, pl. 15 (1854--Figure of the type).

Totanus leucopterus Vieillot, Nouv. Dict. d'Hist. Nat. (Ed. II) VI, p. 396 (1817).

Calidris leucopterus Cuvier, Règne Anim. I, p. 526 (1829).

Tringa pyrrhetraea Lichtenstein, Forster's descr. anim. p. 174 (1844--Otaheiti).

Prosobonia leucoptera Bonaparte, Compt. Rend. XXXI, p. 562 (1850); Sharpe, Cat. B. Brit. Mus. XXIV, p. 525 (1896).

Tringoides leucopterus Gray, Handl. B. III, p. 46 (1871).

Phegornis leucopterus Seebohm, Geogr. Distrib. Charad. p. 452 pl. 18 (1888).