The Alaudidae are generally recognisable by the casing of their metatarsi (p. [496]), but in other respects they seem to shew an affinity to the Motacillidae (Anthinae) on the one hand, and to the Fringillidae on the other. The wing-characters, on which reliance was formerly placed, prove to be wholly untrustworthy.
As to the rest of the "Families" of Oscines, it is impossible to indicate their probable relations by placing them in sequence, or even at present to group more than a few of them with any degree of assurance. Some have not yet been defined at all, and few of them sufficiently for anyone to be confident as to their limits. Thus in the Muscicapidae hardly any two systematic ornithologists will agree as to which genera should be included and which excluded. If restricted to Old World forms, there is still no defined boundary between them and the Campephagidae, while there is perhaps even less distinction between them and the Sylviidae (or Sylviinae, if these last be included among the Turdidae). Moreover, by some taxonomers the Mniotiltidae have been referred to the Muscicapidae, and though there is an obvious distinction between them in the number of the primaries, the instance of the Alaudidae (already mentioned) shews that this may be of very slight importance.
Some other "Families" may perhaps be grouped with less risk of error. The Troglodytidae, Certhiidae, Sittidae and Paridae are possibly such; but the limits of the last-named are certainly not laid down, and it would be hard to give a good reason either for admitting or refusing to admit into it genera like Liothrix or Chamaea, while the puzzle is still greater in regard to some forms from Australia and New Zealand.
The two latest writers on the subject, Dr. Gadow and Professor Newton, abstain from offering any scheme of Classification of the Oscines, the latter limiting himself to the declaration, already expressed by the late W. K. Parker, that the Corvidae should stand as the highest group. As regards their predecessors it will be enough here to enumerate the "Families" in the order in which they were arranged by Dr. Stejneger[[279]] in 1885, and Dr. Sharpe[[280]] in 1891; the scheme of the last author, however, being reversed to harmonize with the plan of the present volume, in which the lower groups are assigned priority. The order of Dr. Stejneger, which is based on both anatomy and morphology, is that subsequently followed, but his Families are not invariably adhered to.
| Dr. Stejneger. | Dr Sharpe. |
| Alaudidae. | Hirundinidae. |
| Motacillidae. | Muscicapidae. |
| [H]Enicuridae. | Campophagidae. |
| Timaliidae. | Pycnonotidae. |
| Leiotrichidae. | Timeliidae. |
| Muscicapidae. | Mimidae. |
| Turdidae. | Troglodytidae. |
| Cinclidae. | Cinclidae. |
| Troglodytidae. | Turdidae. |
| Chamaeidae? | Sylviidae. |
| Mimidae? | Vireonidae. |
| Hirundinidae. | Ampelidae. |
| Campephagidae. | Artamidae. |
| Dicruridae. | Laniidae. |
| Ampelidae. | Regulidae. |
| Artamidae? | Paridae. |
| Laniidae. | Zosteropidae. |
| Vireonidae? | Dicaeidae. |
| Paridae. | Nectariniidae. |
| Oriolidae. | Meliphagidae. |
| Paradiseidae. | Certhiidae. |
| Corvidae. | Mniotiltidae. |
| Sturnidae. | Motacillidae. |
| Meliphagidae. | Alaudidae. |
| Nectariniidae. | Fringillidae. |
| Dicaeidae. | Coerebidae. |
| Certhiidae. | Tanagridae. |
| Coerebidae. | Ploceidae. |
| Mniotiltidae. | Icteridae. |
| Tanagridae. | Oriolidae. |
| Ploceidae. | Dicruridae. |
| Icteridae. | Eurycerotidae. |
| Fringillidae. | Eulabetidae. |
| Sturnidae. | |
| Ptilonorhynchidae. | |
| Paradiseidae. | |
| Corvidae. |
As regards structure, the Oscines have one posterior incision or fenestra on each side of the sternum; the furcula is U-shaped; the tongue is variable, as is the syrinx (pp. [13], [21], [22], [467]); the nostrils may be pervious or impervious; an after-shaft is nearly always present, though comparatively weak; down occurs sparingly on the blind young, and is absent, or only found on the unfeathered spaces, in adults. The primaries number ten or eleven; the secondaries nineteen, twenty, or even more; the rectrices normally twelve. The form of the bill, wings, and tail are discussed under the different Families; the metatarsus exceptionally is smooth in front, but is ordinarily scutellated, while behind it is smooth and generally compressed, except in the Alaudidae, which, having it scutellated posteriorly, are termed scutelliplantar, as opposed to laminiplantar (with one horny growth behind). The hallux is the strongest toe.
Of fossil forms of Oscines, Osteornis (Protornis) of the Lower Eocene of Glarus in Switzerland may be Passerine; Palaegithalus (Sylviinae) and Laurillardia (Sturnidae) have been found in the French Upper Eocene; Palaeospiza (Fringillidae) in the Oligocene of Colorado; Motacilla, Turdus, Lanius, Corvus, Fringilla, and Loxia in the French Miocene or in the Breccia of Italy; Scolephagus and Corvus in the Pliocene of Oregon; Palaeocorax in the Chatham Islands; an extinct Foudia (Fringillidae) in Réunion.
Fam. I. Alaudidae.–The Larks inhabit the Palaearctic, Indian, and Ethiopian Regions, only one genus (Otocorys), with many races, being found in America, and one (Mirafra) in the Australian Region. Of the former, O. peregrina, occurs as far south as Bogota, while the latter is found in Australia and Flores. M. hova is peculiar to Madagascar, M. javanica to Borneo and Java, Spizilauda deva to India. Alauda arvensis, the Sky-Lark, and Lullula arborea, the Wood-Lark, alone breed in Britain: but Otocorys alpestris, the Shore-Lark, is a regular winter-visitor to our shores; while Galerita cristata, the Crested Lark, Calandrella brachydactyla, the Short-toed Lark, and Melanocorypha sibirica, the White-winged Lark, occur occasionally. The Sky-Lark has been introduced into Long Island, N.Y., Australia, and New Zealand.
Fig. 107.–Sky-Lark. Alauda arvensis. × ½.