16 MR. W. K. PARKER ON THE MORPHOLOGY OF 



On the Palate o/^Picumnus minutus. 



This Woodpecker, from Bahia, Brazil, is about the size of our native Golden-crested 

 Wren; it leads on to the lesser group, or the Wrynecks, having soft tail-quills. In 

 several respects it is of extreme interest, especially as relating to the Passerines of its 

 own geographical area, namely those low forms of the Western Notogcea the " Cotin- 

 gidse " and " Pormicariidse." I have had to work out the parts of this bird's palate 

 from the fractured skull in a dry skin, kindly given me by Osbert Salvin, Esq. Labour of 

 this kind was never more richly rewarded. 



The nasal septum (Plate V. figs. 3 & 6, s. n) is semiosseous ; the rest of the labyrinth 

 is principally persistent cartilage. The upper anterior and posterior regions of the 

 septum are all occupied with one continuous bony tract, which also runs into the alse 

 of the lower and trabecular region. 



Between and behind these wings there are three centres of bone, the last of them 

 being the familiar postero-inferior bone of tbe septum, a subterminal trabecular centre. 

 The cranio-facial " notch " is not perfect, and the ossified septum and meso-ethmoid (p.e) 

 are articulated together. 



A distinct " septo-maxillary " (s.mx) could be seen on the left side, and in front of it 

 a thickening of the same nature. The right bone had coalesced with the inner edge of 

 the palatine, that part which receives increment from the palatal process of the prae- 

 maxillary. 



The vomers (figs. 4, 5, v) retain their embryonic (" Rhynchpsaurian ") condition, as in 

 the young of Gecirms viridis (Plate III. figs. 5, 6, v), being arcuate " horns " attached 

 to the mesopterygoid processes of the pterygoid (pg). These latter processes are normal, 

 but shorter than in our native species ; and the rest of the bone is similar to that of 

 Pieus minor, but stouter. 



The palatines, as seen from below (fig. 3, pa, pt.pa), struck me at once as being sin- 

 gular, the postpalatine flanges not being bevelled off, as in the other kinds, but largely 

 developed as in the " Pormicariidse " and " Cotingidae " amongst the Passerines of South 

 America*, and notably also in the Australian Lyre-bird (Menura superba). In these birds, 

 however, Thamnophilus, Pachyramphus, &c. these side walls of the posterior narial tunnel 

 are continuous with the rest of the palatal ossification ; but in Picumnus (Plate V. fig. 5) 

 they are distinct laminae of bone, each with a down-growing ala. 



These "postpalatine" bones end in front behind the " interpalatine " spurs, and 

 below the " ethmo-palatine " laminae, which here, as in the Green Woodpecker, are feebly 

 developed. The interpalatine spurs are well developed, and are more normally placed, 

 further backwards, than in the " Picidae " generally. The rest of the palatine is quite 

 like that of its congeners. The maxillaries (mx) have a very rudimentary maxillo- 

 palatine process (mx.p) ; and the separate " palato-maxillary " (p.mx) on the left side is 

 represented by an enlargement of the inner edge of the bone, which was once, most pro- 

 bably, quite separate. 



* I cannot give illustrations of these Passerine structures here ; they are freely given in the first part of my paper 

 on the " iEgithognathse," about to appear in the ' Zoological Transactions.' 



