310 PROF. W. K. PAEKBE ON ^GITHOGNATHOUS BIRDS. 



together ; they coalesce with the ascending palatine plate. The thickened shoulders 

 of the vomer are bevelled off; and here it is seen that the bony matter has ossified only 

 the posterior clavate portion of the vomerine cartilages (compare PI. LVII. fig. 2, v, v.c, 

 with VI. LIV. fig. 8, V, V. c). The bony substance of the vomer is in immediate contact 

 with the inturned alinasal lamina {i. a. I), but does not run into it ; the same may be 

 said of the small, triangular, apiculate " septo-maxillaries," which are attached (one on 

 each side) to the posterior border of the nasal cartilage, where it overlaps the vomerine 

 cartilage. These modifications form an exact half-way between the Crow and the 

 Hemipod. These form the first variety of " complete segithognathism," these parts 

 in this type being quite distinct, the septo-maxillary grafting itself on the scarcely 

 ossified vomerine cartilage, and not on the inturned alinasal wall (PL LVII. fig. 2, i. a. I, 

 V. c, s.nix, v). 



The " maxillo-palatine processes " (figs. 1 & 2, mx.p) are simple, flat, pedate out- 

 growths of the maxillaries ; and in Pi^ra they do not bind tightly against the vomer, 

 as in those next to be described, but lie on a considerably lower plane. Behind these 

 processes, the maxillary continues broad for some distance, and then becomes filiform, 

 running without any suture into the jugal (J). 



In the endo-skeletal elements of the second arch we have a subtypical condition of 

 the parts. The epipterygoid process of the pterygoid (e.jyg, J^g) is not much developed ; 

 but the bones themselves are thoroughly passerine, the flat anterior head articulating 

 with its own segment, the mesopterygoid, which is now confluent with the palatines. 



The palatines (fig. 1, t.2}a, jir.j^a, pt.pa) are very instructive ; they are strongly bowed 

 out behind the short, straight prsepalatal portion ; but the angle is small, square, and 

 notched. This transpalatine process (t.pa) was evidently formed in a very slight angular 

 cartilage ; and I much doubt its having had a separate bony centre. 



The interpalatine spurs (i-jJa) are very large and spinous ; and the concave bridge of 

 bone between these and the angular process is of greater extent than the upper or 

 ethmo-palatal lamina, which sends a small spur along the outer edge of the vomer. 

 The postpalatal laminae (pt.pa) meet each other below the parasphenoidal rostrum 

 [pa.s), and are greatly enlarged, orbitally, by the mesopterygoid segment. 



The lacrymals are, I believe, corvine (but are lost in this specimen) ; and so is the 

 ethmoid {])■]))■ As in Memira, the passages for the first and fifth nerves are not distinct, 

 one broad roadway, very wide on the inside, existing between the upper edge of the 

 thick spongy antorbital and the ethmoidal roof. 



The vertical width of the antorbital is small inwards ; but it is flush with the face, 

 and very massive outside and below (see fig. 1, p.p, where it is indicated by fainter 

 shading). I have not found any separate " os uncinatum ;" it may have been lost with 

 the lacrymal. 



Example 5. PachyrhampJms 1 



Habitat. Gnmn?!.. Group " Tracheophonse," Mliller ; family " Cotingidse." 



4 



