338 PKOF. W. K. PAEKEK ON tEGITHOGNATHOTJS BIRDS. 



Australian passerines, and that whether their song-muscles are developed or not. In 

 this first paper I have only space for one more of these, namely Pachycejahala; but 

 afterwards Sittella and Sericornis will come under notice, besides those very unique types 

 Ptilotis and Acanthorhynchus. 



Example 25. Pachycephala fusca {Vj. 



Habitat. Australia. Group " Oscines," Mliller ; family " Laniidse." 



Notwithstanding the superiority of this type over Petroica in the separation of the 

 tracheal muscles for song, it is yet, I am satisfied, on the whole, only a slightly modified 

 Petroica. Its large skull, shortish beak, and most remarkable vomer are the proofs of 

 this. In some respects, Pachycephala is less specialized than Petroica — that is, in its 

 palatine arch, both the primary and investing parts. 



On each side of the basitemporal there is the tubular " tympanic" on the " sipho- 

 nium," with one or two additional ossicles. The basitemporal (PL LXI. fig. 7, b.t) 

 itself is bat-shaped, as in the " Cotingidae " and " Formicariidse ;" and there are no basi- 

 pterygoids on the rounded parasphenoidal beam. The hinge is almost perfect. The 

 septum nasi (s. «) is alate in front ; and the trabecular bone {tr) has appeared in this part 

 behind the alse. The recurrent alinasal fold {re. c) is well marked, and the inturned 

 alinasal fold [i. a. I) is nari-ow ; mesiad of this we see the huge alinasal turbinal (a. tb) 

 with two bony patches. The alinasal scale (Plate LXI. fig. 8, al.n) externally is unos- 

 sified, but of large extent. The inferior turbinals are narrow and very long (i. tb) : they 

 are mostly soft ; but there is a bony patch postero-superiorly. 



A hasty observation might lead to the opinion that the peculiar form of the vomer 

 (like baggy Turkish trowsers) was a mere fi-eak of Nature ; but its meaning lies deeper 

 than this. In Petroica monticola (PI. LX. fig. 9, v, s.mx), we have the same form, 

 coupled with an alinasal turbinal ossicle close to the angle of the vomer. This curious 

 outgrown form depends upon the very large size of the supero-lateral elements, the 

 septo-maxillaries (s.mx), which here rival those of Lizards and Snakes. The vomer is 

 subcarinate in front, but does not project at the mid line ; the bone, especially at its 

 edges, is thick and spongy ; its upper lobes are scarcely developed : altogether it is a 

 slightly masked reptilian structure. 



The pterygoids (PL LXI. fig. 7) are like those of Petroica, but shorter; they have, 

 like the palatine arch, altogether a very cotingine appearance. 



The postpalatine keels are sharp and deep ; the mesopterygoid and ethmo-palatine 

 laminse are low, the interpalatine spurs abortively developed, as is the transpalatine (t.pa), 

 the bony bridge across of slight extent, and the prsepalatine bar a narrowish subsinuous 

 bar. The maxillo-palatine processes {mx.p) are broad-based, thick and clumsy, not so well 

 developed as in Petroica (PL LX. figs. 9 & 10, tnx.p), and on a level with those of 

 Pachyrhamphus (" Cotingidae") and Thamnophilus (" Formicariidse"). The continuously 

 bony jugum {j) is feeble and sinuous, and but little inturned behind. The prsefrontal. 



