AND OTHER EXTINCT BIRDS OP MAURITIUS. 293 



The shortest humerus is 8'5, the longest 92 mm. in length. They all differ from 

 that oi Aphanapteryx by being far less curved, stronger throughout, and furnished with 

 a lai'ge pneumatic foramen ; the sulcus transversus upon the head of the humerus is 

 deeper, but the tuberculum medium is lower. 



The cervical vertebrae of the Rallidse can be easily recognized by their shape and by 

 the numerous articulating facets, processes, and median crests. On the whole, these 

 vertebrae of F. newtoni resemble more closely those oiPorphyrio and Ocydromus than 

 those of Fulica proper. Dorsal spinous processes are absent in the 9th and 10th 

 vertebrae, they are rather low in the 6th and 5th, sharp and high in the 4th. Ventral 

 median processes are absent in the 10th to 5th, high in the 4th and 3rd. The latter 

 two vertebrae are marked by a deep round notch on each side, this notch being often 

 turned into a complete foramen. Most of the lower and middle vertebrae of the neck 

 are very broad in comparison with their length. 



In conclusion, we feel inclined to think that the Fulica newtoni combines important 

 characters of the true genus Fulica with those of Porphyrio, Trihonyx, and Ocydromus, 

 and that on the whole it more resembles these last three than the true Waterhens. 



10. Aphanaptertx brokcki. (Plate XXXV. figs. 12-20.) 



Only the tibia, tarso-metatarsus, and underjaw were hitherto known, described and 

 figured by M. Milne-Edwards. Besides the tibiae and taiso-metatarsi of many indi- 

 viduals, we have now before us the pelvis with sacrum, femora, and humeri; one 

 sternum, one third cervical vertebra, and one nearly complete premaxilla, together with 

 fragments of the upper and lower jaws. It has been comparatively easy to determine 

 most of these new bones because of their close resemblance to the corresponding parts 

 of Erythromachus. 



The pelvis, with the sacrum, of one specimen is extremely well preserved. It is much 

 more compact, stouter, shorter, and broader than that of Fdica newtoni ; the dorsal 

 margin of the pre-acetabular part of the ilium reaches up to the dorsal spinous crest of 

 the anchylosed presacral vertebrae, as is also the case in Ocydromus and Porphyrio. In 

 their general configuration the pelvis and sacrum of Aphanapteryx agree with Erythro- 

 machus. 



The femur, essentially similar to that of Fulica, Porphyrio, and other allied Rails, 

 can be distinguished from that of Fulica newtoni by its smaller dimensions. 



The tibia and metatarsus, having been described and figured previously, need not be 

 commented upon, beyond stating that they, especially the metatarsus, are relatively 

 stouter than those of Fulica. 



The sternum and humerus are of particular interest, because of their small size, and 

 because of the absence of any large pneumatic foramina, indicating that this bird was 

 devoid of the power of flight. The sternum is not complete, its posterior portion being 

 absent. Its width across the level of the first rib behind the anterior lateral process is 

 only 25 mm. ; the keel is very much suppressed, with its anterior margin broadened 



