44 NEORNITHES RATITAE chap. 



sense ; Ijut 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. Eemains of various forms, chieliy of 

 gigantic size, have been disinterred from the Miocene strata of 

 Santa Cruz in Patagonia, one of which (FhororhacJws) 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, Seilores 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 N^ewton's Dictionary of Birds. In a review of Dr. 

 Ameghino's paper on these birds,^ Mr. C. W. Andrews stated that 

 Phororhaclws and others of the " Stereornithes " were not truly 

 Eatite, 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 {Dicliolophvs). 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. Mesemhriomis) 

 are perhaps truly Eatite, and one at least {Dryornis) belongs to 

 the Cathartidae. Phororhaclws 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 A-pUryx, and, to a considerable extent, to the Dinorni- 



1 Bol. Mus. La Plata, i. 1887, p. 24. "- Rcvist. Argent, i. 1891, p. 255. 



^ An. Mus. La Plata, Pal. Argent, i. 1891, pp. 20, 37. 



* Revist. Argent, i. 1891, pp. 441-453. 



^ Bol. Inst. Gcogr. Argent, xv. 1895, pp. 11, 12. 



Ibis, 1893, pp. 40-47 ; and Xat. Sci. 18^4, p. 125. 



^ Ibis, 1896, pp. 1-12 ; see also Gadow, op. cit. pp. 586, 587. 



Science Progress, v. 1896, pp. 398-416. 



