1895.] LOEIUS FLWOPALLIATITS AND PSITTACUS EBITHACUS. 319 



physes (pz) look dorsad, rnesiad, and almost slightly postaxiad, and 

 so contrast strongly with those of the fifth vertebra. As they do 

 not extend so much forward, the anterior ends of the lateral arterial 

 canal (ac) are visible when the vertebra is viewed dorsally. The 

 hypapophysis has disappeared, but the structure of the pleur- 

 apophysial lamella is otherwise much as in the fifth vertebra, save 

 that the foramen (/) formed by its superior postaxial process is 

 larger. In P. erithacus the conditions are similar, except that the 

 neural spine is not so obsolete. In this species the sixth vertebra 

 is the first and only one to have a lateral foramen (/) formed by 

 the process of the pleurapophysial lamella. The catapophyses (c) 

 are rather more marked than in the fifth vertebra. In both 

 species the metapophyses (m) are prominent. 



The seventh vertebra of L. jlavopalliatus is very like the sixth, 

 and the same may be said in the case of P. erithacus, except that 

 in the latter species there is no lateral foramen and the pleurapo- 

 physial processes (st) are longer. In both, the catapophyses (c) 

 are more developed than in the preceding vertebra and project 

 preaxiad as well as ventrad. In both, the metapophyses (»i) are 

 as well developed as before. 



The eighth vertebra has the catapophyses (c) again more pro- 

 minent and approximated, and they are at their maximum. In 

 L. jlavopalliatus the hyperapophyses (hp) have almost disappeared, 

 and hardly less so in P. erithacus. In both they have again receded 

 and stand upon the postzygapoph}^ses. 



In the ninth vertebra the hypapophysis (h) suddenly reappears 

 and is of large size in both species. The neural spine also re- 

 appears of considerable size, and is quadrate in shape in P. erithacus, 

 but it is only represented by a very low and delicate ridge in L.flavo- 

 palliatus. In both species the postzygapophyses are shorter and 

 less diverging than in the eighth vertebra. In L. jlavopalliatus 

 the lateral^ foramen (f) has become sUghtly smaller. In both 

 species the metapophyses (»n) are rather more developed and are 

 indeed at their maximum. In L. jlavopalliatus there are still 

 hyperapophyses (hp) on the postzygapophyses. 



In the tenth vertebra the lateral foramen disappears in L. jlavopal- 

 liatus, and the postaxial margin of the pleurapophysial lamella {pi) 

 develops two processes projecting postaxiad and slightly ventrad. 

 The neural spine (»i) for the first time reappears as a distinct, though 

 smaller pointed process. The postzygapophyses {ptz) are smaller 

 than in the preceding vertebra, only projecting about as much back- 

 wards as the prezygapophyses do forwards. The hypapophysis (Ji) 

 is much as in the ninth vertebra. In P. erithacus it is rather 

 smaller than in the preceding vertebra, slightly bifurcating at its 

 distal end, and the neural spine is certainly smaller. In both 

 species the metapophyses (m) are rather smaller. 



The eleventh vertebra in L. jlavopalliatus bears a distinct, quadrate 



* Not the canal enclosed by the pleurapophysial lamella as a whole (that 

 persists on into the eleventh vertebra in both), but only that enclosed by the 

 delicate upper postaxiad process of that lamella. 



