164 DR. C. W. ANDREAVS ON FOSSIL BIRDS [Jan. 19, 



present specimen only the anterior end is preserved. The syn- 

 sacrum is repi'esented by about fourteen vertebra3. Tlie acetabulum 

 is large and nearly circulai- in outline ; its ventral border lies 

 above the ventral surface of the synsacrum. Tlie acetabular 

 foramen is a lai'ge, roughly triangular opening thi'ough which the 

 ai'ches of the vertebi'a3 of that I'egion can be seen : the anti- 

 trochanter is very large. The i'egion of the pectineal process is 

 much abraded. Only the proximal portions of the ischia and 

 pubes are presei'ved ; they are intima,tely fused with the centra of 

 the synsacral vertebra3, which, as described below, thei'e form a 

 ventral prominence. There is no very definite ridge uniting the 

 two ischia aci'oss the synsacrum as in some specimens of the pelvis 

 of yEjjyornis, and therefoi'e the postsacral furrow of Bui'ckhardt 

 is scarcely at all developed. 



In the syncracum there are eleven or twelve vertebi'a3 in front 

 of the true sacrals. Of these the seven anterioi' lie in fi'ont of 

 the acetabulum and the point of oi'igin of the pubes ; the other 

 four 01' five are crowded together between the acetabula, and are 

 so closely fused with one another that they can only be distin- 

 guished fi-om one another by the foramina perforating their fused 

 arches. 



The fii'st synsacral bears a facet for a rib-head, situated on the 

 side of the centrum close to the anterior ai'ticular surface : the 

 transverse process has been broken away. The base of the neural 

 arch is excavated by a deep pocket-like fossa. The neuiul spine 

 is broken away to a great extent, but it can be seen that its base 

 was strengthened by six buttress-like lamellae of bone, of Avbich 

 two are placed longitudinally, two othei'S ru.n outwards and a 

 little foi'wards on to the ti'ansverse pi'ocesses ; the two remaining 

 ridges run midway between the last-mentioned plates and the 

 postero-median one. There is a small hypapophj^sis situated 

 immediately behind the anterior surface of the centrum. 



The second vertebiu has a broad transvei'se process the base of 

 which is excavated by a large pneumatic fossa divided into two 

 chambers by a vertical lamella of bone. There seem to have been 

 no articular surfaces for ribs, but the bone is somewhat incomplete 

 where they should occui-. There is a very slightly marked hypa- 

 pophysis on the front of the ventral surface. The next A^ertebi-a is 

 similar except that there is no trace of a, hypapophysis. In the 

 next the transverse process is smaller and more backwardly directed, 

 but it is not, as in ^^jnjoi'nis, divided into a dorsal and ventral bar. 

 This division, however, occurs in the next (5), in which the ventral 

 bar is small and forwardly directed. The same is the case in the 

 following two (6 and 7). In none of these hinder vertebrae (3-7) 

 is there any hyjjapophysis. The outer ends of the parapophyses, 

 which are separated by oval foramina, are intimately united with 

 the ilia. 



The centra of the eighth to the eleventh (or twelfth) vertebrje 

 are fused with one anothei- and with the proximal poi'tions of the 

 pubes and ischia. The united centra form a ventral prominence 



