44 NEORNITHES RATITAE CHAP. 
sense ; but it should be noted that their systematic position was not 
by any means assured, though justified by what was then known 
of these extraordinary fossils, of which the sternum has not even 
yet been brought to light. Remains of various forms, chiefly of 
gigantic size, have been disinterred from the Miocene strata of 
Santa Cruz in Patagonia, one of which (Phororhachos) was described 
in 1887 by Dr. Ameghino,’ from its mandible as an Edentate 
Mammal, though four years later? he arrived at the more correct 
conclusion that the jaw was to be referred to a bird. In 1891, 
moreover, Sefiores Moreno and Mercerat® proposed a new Order 
with the name of Stereornithes, when publishing a series of fine 
plates; while Dr. Ameghino, who criticised their work, reduced 
the nine genera created therein to the smaller number of three.* 
Another paper by the author last named,’ and two by Mr. 
Lydekker ° should be consulted by those interested in the details 
of the subject, while an admirable summary will be found in 
Professor Newton’s Dictionary of Birds. In a review of Dr. 
Ameghino’s paper on these birds,’ Mr. C. W. Andrews stated that 
Phororhachos and others of the “Stereornithes” were not truly 
Ratite, but were Carinate forms in which the wings had under- 
gone reduction, and suggested that possibly they were related to 
-the parent stock of the Gruiformes, approximating particularly 
to Cariama (Dicholophus). Shortly afterwards Dr. Ameghino’s 
collection was acquired by the British Museum, and a study of 
the specimens themselves has not caused the reviewer to change 
his opinion.” Some members of the group (e.g. Mesembriornis) 
are perhaps truly Ratite, and one at least (Dryornis) belongs to 
the Cathartidae. Phororhachos is remarkable for the immense 
size and heavy build of the skull, to which the legs, huge though 
they sometimes are, bear no proportion; the maxilla is exceed- 
ingly compressed, yet very deep, and ends in a strong hook, while 
the long massive mandible curves upwards to meet it. There is 
a quite or nearly complete interorbital septum in this case, as 
opposed to Apteryx, and, to a considerable extent, to the Dinorni- 
1 Bol. Mus. La Plata, i. 1887, p. 24. 2 Revist. Argent. i. 1891, p. 255. 
3 An. Mus. La Plata, Pal. Argent. i. 1891, pp. 20, 37. 
* Revist. Argent. i. 1891, pp. 441-453. 
> Bol. Inst. Geogr. Argent. xv. 1895, pp. 11, 12. 
6 Ibis, 1893, pp. 40-47 ; and Nat. Sci. 1894, p. 125. 
7 Ibis, 1896, pp. 1-12; see also Gadow, op. cit. pp. 586, 587. 
8 Science Progress, v. 1896, pp. 398-416. 
