Art. XXXI.—Notes on a New Species of Rail, Rallus pictus, Painted Rail.
[Read before the Philosophical Institute of Canterbury, 5th April, 1871.]
Early in the month of March there was received at the Canterbury Museum a fine specimen of the Rail family, which had been obtained in the neighbourhood of the Okarito lagoon, Westland. This handsome bird at first sight bears a strong resemblance to Rallus pectoralis, Gould, from the similarity in the colours and markings of its plumage; a closer examination discloses its superior size and more slender figure, some difference in the shape of the bill, and a well defined garter above the tarsal joint, thus showing a marked departure from the form of its better known congener.
The bill differs from that of R. pectoralis, in presenting a form less wedge-like, more produced, with the culmen slightly raised, the shallow furrows in which the lateral nostrils are pierced are less angular, the organ also possesses a greater degree of flexibility; that it is comparatively weaker one may judge from the relative measurements of the bills of the two species.
|R. pectoralis.||R. pictus.|
|Length of upper mandible from gape||1.42||1.58|
|Length of under mandible from gape||1.31||1.54|
|Width of bill at base||0.29||0.25|
|Depth of bill at base||0.38||0.29|
|Entire length from point of bill to the end of tail||12.25||15.75|
In addition to the peculiarities of the bill thus pointed out, it possesses a leg better adapted for wading than that of the closely allied species, the tibia is bared of feathers to the width of half an inch above the tarsal joint. It is not surprising that amidst the dense tangled thickets of rush, grasses, or Carex that border the swampy lagoons of the West Coast, it has hitherto generally eluded observation; the shy, retiring habits of the group to which it is allied would there find abundant shelter for concealment, whilst its slender form, its compressed almost canoe-like figure, is wonderfully well fitted for rapidly
threading the intricate mazes of the rank aquatic or semi-aquatic vegetation amidst which it finds its food. From its short concave wing, it is evident it must depend less on securing safety by flight than on the rapidity with which it can conceal itself from notice amongst the marshy vegetation of its favourite haunts. If the bill of R. pectoralis may be said somewhat to resemble that of Ocydromus, that of R. pictus rather shows an approach to that of R. aquaticus, Penn., less produced. We have heard on very good authority that a larger species of rail is yet to be found amongst the morasses of Westland.
Bill, upper mandible dark horn colour, lower mandible lighter; crown, occiput, and nape, olive brown marked with black; from the base of the upper mandible, a narrow line of white passes in almost a straight line above the eye, merging into pale grey as it descends obliquely towards the nape; a broad stripe of chestnut commences at the base of the bill, passes through the eye, across the cheek, and meets in a broad band at the back of the neck, forming a richly coloured tippet widest on the back of the neck; lower part of the cheek and throat pale grey and brownish grey; chin greyish, almost white; lower part of throat and breast black, each feather marked transversely with two bars of white indistinctly tipped with pale brown; breast crossed with a band of rich but light brown, with a chesnut spot in the centre, basal portion of each feather black, apical portion crossed with two narrow black bars, shafts white; greater wing coverts, olive brown, with occasional white and black spots; point of shoulders nearly white; primaries, of which the second, third, and fourth are nearly of the same length and longest, third and fourth chestnut, barred on inner and outer web with black, first and second marked with bars of white, which, on inner web are slightly crescentic; abdomen black, barred with white; lower abdomen pale fulvous; front of thighs fulvous; back of thighs slaty black; tail, shafts black, webs olive brown, darkest in the centre, middle feather with four spots of white, centre feather of under tail coverts black, with three white bars tipped with fulvous; vent black, tipped with deep fulvous.
Bill, from gape to tip of upper mandible, 1.58 inches; wing, from flexure, 6.17 inches; tarsus, 1.67 inches; middle toe and claw, 1.58 inches; hind toe and claw, .5 inch; tail, 2.75 inches; extreme length from tip of mandible to tail, 15.75 inches.