On Ægithognathus birds. Pt. I / by W.K. Parker.

  • Parker, William Kitchen, 1823-1890.
Date:
[1875?]
Catalogue details

Licence: Public Domain Mark

Credit: On Ægithognathus birds. Pt. I / by W.K. Parker. Source: Wellcome Collection.

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    American types; it is as if its father had been a Grallaria and its mother a Pitta, but to become an Artamus it had risen higher in the ornithic scale than either of its parents. Example 10. Hendrocolaptes albicollis, Yieill., 6. Habitat. Brazil. Group “ Tracheophonse,” Muller ; family “ Dendrocolaptidse.” Mr. Salvin’s collection yields me five types of this kind of Southern passerine, in which the segithognathism is of the first or distinct variety of the complete kind; the members of this family and of the “ Tyrannidae ” seem to me to stand near to, but in reality higher than the “ Formicariidse1 speak thus, however, rather of their facial morphology than as an ornithologist. In some of these, as in my present instance, the basipterygoids are indicated by spurs of the basitemporal (PI. LIX. fig. 1, b.t, b.pg). At first sight this seems a trifle; but morphology has no trifles: it is a Lacertian stigma. Every student knows that the innermost laminae of the massive “ parosteal ” basitemporals of the bird become the practical symmorphs of the Lizard’s basisphenoids—symmetrical ectostoses; also that, whilst in the bird the basipterygoids are ossified by the parasphenoidal rostrum, in the Lizard they are hardened directly from the basisphenoids. In our ascent from the less developed to more highly metamorphosed types, we constantly come across this “ changing of hands,” in the finish of a part. That Hendrocolaptes should have the Lacertian character is like a touch of “ atavism; ” it can scarcely be other than a delicate link in a long evolutional chain. The strong, rounded parasphenoid (PI. LIX. fig. 1, pa.s) is short in this long-faced bird ; it forms the underbalk to a very massive, non-fenestrate inter orbital septum. The ossification of the nasal labyrinth is very similar to that of Grallaria; but I find no trabecular bone; the upper septal ossification is less; and so is that behind, on the upper turbinal; that on the inferior turbinal is larger. The alee nasi outside are quite soft; but their turbinals have each a long endosteal tract, as in Grallaria (see PI. LYI. fig. 9; and PI. LIX. figs. 1 & 2, a. tb). I find no subnasal alse to the thin knife-like cartilaginous septum nasi: the fenestra separating it from the meso-ethmoid (fig. 3,p. e, c.f. c, s. n) has become a “ notch” by extension downwards of the cleft, such a closed cleft as is seen in Grallaria (PI. LYI. fig. 10, c.f. c). In this respect Hendrocolaptes has risen above those “ Formicariidae; ” but in its aegithognathism it is below them ; for I cannot find any advance of the bony matter of the vomer into the turbinals; it stops quite short. The vomer (v) is very curious, its coalesced part being very wide and short, and its legs almost close together. A small septo-maxillary (fig. 2, s.mx) is seen intervening between the outer angle of the upper vomerine lobe and the extremity of the alinasal turbinal. The flat, broad, closely clinging vomerine crura are ankylosed to the ethmo-palatine plates; the angular process on each side, in front, is articulated obliquely and strongly to the maxillo-palatine, in the manner of a zygapophysis. The ankylosis of the secondary bones of the upper jaw