BIRDS. 1C1 



Family" RAILING." 



Example. Gallinula chloropus, Lath. 



These birds, which range in size from that of a Quail to the bulk even of a Cassowary, 1 are 

 very easily characterised ; and form a neat group. They have very compressed bodies, and very 

 feeble wings, and this peculiarity in their form and structure so modifies their Shoulder- and 

 Breast-bones as to mask their relationships. In their skull and face they differ very little in 

 essentials from the Cranes ; and in their skeleton, generally, they intervene between these birds 

 and the Plovers, it being more pneumatic than the latter, and less so than in the former. 

 Whilst acquiring no higher cerebral development than the Ostrich tribe, they differ from them, far 

 more than do the Plovers, in the structure of their skull, having, like the Cranes and the Bustards, 

 the " anterior pterygoid processes " aborted. They agree with the Gallo-struthious group, with 

 the Herons, and with, the genus Podiceps, towards which they seem to lead in the absence of 

 the " lateral occipital fontanelles," so largely distributed in the Wading, Swimming, and Diving 

 Birds. Connecting links must be looked for between the Rails and the Kagu on one hand, and 

 between the Grebes and the Coots on the other : they have also no little affinity for the Herons. 

 The Shoulder-girdle and Sternum of Gallinula is shown in Plate XV, fig. 4, magnified six 

 diameters : the dissection was made from a half-ripe embryo. The scapula (sc.), which is only 

 partially cloven from the coracoid, is extremely slender and long ; it is moderately arcuate, and 

 almost runs to a point in the supra-scapular region (s. sc.) ; about half of the scapula is invested 

 with bone. The meso-scapula (m. sc.) is blunt and short, and it has given off a delicate bar of 

 cartilage (m. sc. s.), and in fig. 5 it is shown as magnified forty diameters. The coracoid (cr.) is 

 shorter and broader than in the adult ; it is only half covered by the ectosteal layer ; its un- 

 ossified regions show the breadth of the meso-coracoid ledge (m. cr.), both above and below, 

 and that the " foramen" pierces the cartilage, as in the Crane. In the old bird the meso-coracoid 

 ledge is continuous, but it is sharply developed, as a crest pointed above, on the lower third of 

 the inner margin of the bone. As in the Pluvialines, the epi-coracoid (e. cr.) is well developed, and 

 hooked ; these parts, however, do not nearly meet and overlap on the edge of the Sternum, but 

 continue far apart, as in the weak-chested Kagu. The furcula is between a U and a V in shape, 

 and is very slender ; each ramus dilates where it meets its fellow (see fig. 6 cl.) ; but there is no 

 inter-clavicle: in the old bird the line of junction is produced upwards, as in the Herons, but not 

 to the same degree. The tips of the furcular rami are knobbed by the addition of the meso- 

 scapular segment, but they are very little decurved not so much so as in the Kagu. Seen 

 laterally, the clavicles of the Gallinule are more curved than those of the Kagu, but are straighter 



1 I include the lately extinct New Zealand forms ; I have already shown (' Phil. Trans./ 1866, 

 p. 163) that the Dinornis casuarinus, or Aptornis of Professor Owen, was a gigantic Rail, and I am 

 fully satisfied that his new genus Cnemiornis (see ' Zool. Trans./ 1866, vol. v, part 5, pp. 395 J04, 

 pis. 63 67) was nothing more or less than a giant of the Rail-tribe, and perhaps owned the well- 

 known pick-axe-shaped head, supposed to have been useful in stubbing-up fern-roots. 

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