PTEROTOCHOS ALBICOLLIS. Kittl. (Male.)
Trachea, tongue, œsophagus, gizzard, and liver of the same form as in Pterotochos Tarnii. The contents of the gizzard also did not differ.
| Inches | |
|---|---|
| Length of intestinal canal | 14½ |
| from cæca to cloaca | 2½ |
| Length of gizzard | ¾ |
| Breadth of ditto | ⅝ |
Only the body, after skinning, of the species, was brought home by Mr. Darwin.
The skeleton of this species does not differ in anything but admeasurements from that of Pterotochos Tarnii; the pelvis, however, being so much damaged in that species, that I was not able to make many notes upon it, I shall give a description of that part in the present one.
Pelvis of moderate size; the ossa pubis and ischium much expanded, and elongated posteriorly, and placed nearly perpendicular to the plane of the ilium, ischiatic foramina large; two large processes arise on the ilium on each side of the junction of the caudal vertebræ for the attachment of the levator muscles of the tail.
| lines | |
|---|---|
| Length of pelvis | 14 |
| Breadth posteriorly | 8½ |
| anteriorly | 4 |
| Length of sternum | 9½ |
| Breadth of ditto | 7 |
| In the narrowest part | 5½ |
| Depth of keel | 2½ |
| Length of coracoids | 7½ |
| Breadth of scapula in the widest part | 1 |
| No. of cervical vertebræ, wanting. | |
| dorsal ditto, wanting. | |
| sacral ditto | 9 |
| caudal ditto, wanting. | |
Remarks:—Both this and the foregoing bird are most curious; it is difficult to say in what order they ought to be placed, the external form being equally ambiguous with the internal structure.
The digestive organs nearly agree with that of many insessorial birds; the pelvis also approaches nearly in form to that of the thrush; the sternum, however, differs altogether from any form found in that order, and is precisely that of a Picus. The coracoids are lengthened; the os furcatum is furnished with only a slight process where it approaches the sternum, in which particulars, also in the form of the ribs, it agrees with the Picidæ.
Having found the internal structure so curious, and so contrary to what I expected, I was led to examine the external more minutely than I had before done. The same form of claw is found in several species among the cuckoos, in the genus Pelophilus, for instance; the two outer toes are zygodactyle, being united together as far as the first joint; the bill, at first sight, might be taken for that of a gallinaceous bird; but in searching among the order Scansores, for some resemblance, I find the same structure in several of the cuckoo family, with the exception of the nostrils being nearer to the apex of the bill in Pterotochos. The Australian genus Menura is, probably, allied to this, but differs in the structure of the nostrils.[[32]]