788 
ME. W. K. PAEKEE ON THE STEUCTUEE AND 
The nasal branch of the ophthalmic has left its burrow in the hinder part of the 
septum nasi, which has bridged it over both above and below. 
The rather strong septum nasi (fig. 7, s.n .) ends in a rounded manner in front, and 
still retains, as a rostral process, the fast-diminishing prenasal or snout-cartilage (p.n.). 
The swelling alinasal folds ( al.n .), with their internal turbinal plate ( al.t .), are best 
seen in fig. 8 ; and in it also can be seen the “ pars plana ” (p.p.), or lower part of the 
prefrontal plate. 
The outer nasal wall (Plate LXXXIY. fig. 6, o.n.w .) and the prenasal bar (p.n.) are 
clearly seen from below, in the fore part of the palate. 
The palatines (figs. 6 & 8, pa.), the pterygoids (p.g.), the quadrate (q.), and the stapes 
( st .) have all made a great approach to the adult condition. The pterygoids and palatines 
are well ossified ; but the former have a cartilaginous cup for articulation with the qua- 
drate, and a meniscoid plate (fig. 11, p.g.) for articulation with a similar disk on the 
anterior pterygoid process (a.p., r.b.s.). 
The meniscus which articulates the pterygoid to the basipterygoid facet is composed 
of typical hyaline cartilage (fig. 12, 200 diam.) ; this is separated from another tract of 
cartilage in immediate contact with the bone-cells ; towards the fissure the cells are very 
much flattened ; those in contact with the endosteal deposit are baggy simple cartilage- 
cells. Hence it is evident that this facet of the pterygoid is a proper segment of carti- 
lage, and not a mere remnant of the main rod such as is seen on the quadrate end of the 
pterygoid. 
The Fowl agrees with the Struthionidse in having no mesopterygoid, contrary to what 
I once supposed (see -Zool. Trans., vol. v. p. 157); in the Anatine series it exists as an 
exogenous spur to the pterygoid ; in other Carinatse it is segmented off. 
The axis of the mandible (Plate LXXXIY. figs. 7 & 8, art., m.Jc.) has acquired an 
ectosteal ring round its internal angular process (“ manubrium mallei ”) ; all the rest is 
soft, and the anterior end of this cartilage has begun to shrink (fig. 7, m.Jc.) ; this is an 
anticipation of what becomes of its counterpart (“ processus gracilis mallei ”) in the 
Mammal. 
The stapedial shaft-bone (st.) is shown in figs. 8 & 10. 
The ectosteal sheaths of the “ basihyal” and “ branchials” have advanced considerably. 
Part of the fibrous skeleton has been described in connexion with the basisphenoidal 
“ stock ” on which it is grafted ; the rest of the splints are easily separable from the 
primordial cranium. 
One pair only of these have coalesced at the mid line : these are the premaxillaries 
(fig. 6, p.x.) ; these have already become truly Gallinaceous, although in a generalized 
manner they have the “ habit” of those of the adults of the lower types. In figs. 6 & 7 
it is shown how these bones are causing, as it were, the absorption of the axis (p.n.) on 
which they were modelled*. 
* This is in conformity with what is so common in the building-np of the skull and face in the Warm-hlooded 
Vertebrata — the “hoarding” and the “ scaffolding” being formed subsequently to the proper walls and gates, 
which walls and gates have to be taken down to a great extent to let the hoarding and the scaffolding stand alone 
