308 DR. H. GADOW ON THE SPECIES OF RHEA. [Mar. 17, 



6. On the Anatomical Differences in the three Species of 

 Rhea. By Hans Gadow, Ph.D., M.A. Cambridge. 



[Eeceived March 17, 1885.] 



In the spring of 1883 the Museum of the University of Cam- 

 bridge received from the Zoological Society of London two specimens 

 of Rhea darwini and one of Rh. macrorhyncha, with the under- 

 standing that I should compare examples of the three species of 

 Rhea hitherto known with each other, and point out their anatomical 

 differences, provided there were any. The comparison made in the 

 following pages must, however, necessarily be incomplete, because 

 some of the specimens were imperfect and were of different ages and 

 sexes. The material at my disposal was the following : — 



One specimen of Rh. macrorhyncha, immature, with most of the 

 viscera removed previously. 



One specimen of Rh. darwini, (S , not quite adult ; skeleton and 

 viscera complete. 



One specimen of Rh. darwini, $ ; skeleton complete, viscera 

 partly removed previously. 



Rh. americana. Several skeletons and preparations of visceral parts 

 in the collections of the Universities of Cambridge and Heidelberg, 

 and in the Museum of the Royal College of Surgeons of England. 



Literature. 



ScLATER, P. L. On the Rheas in the Society's Menagerie, 



with Remarks on the known Species of Struthious Birds. 



P. Z. S. 1860, p. 207. 

 . On the Struthious Birds living in the Society's Mena- 

 gerie. Trans. Zcol. Soc. iv. p. 3.53, pis. 68-70 (I860). 

 Booking, A. Monographie des Nandu oder Siidamericanischen 



Strausses {Rhea americana). Arch. f. Naturgesch. 1863, 



p. 213. 

 The same under the title of : — De Rhea Americana : Dissertatio 



Zoologica. Bonnse. 

 Cunningham, R. O. Notes on some Points in the Osteology of 



Rhea americana and Rhea darwini. P. Z. S. 1871, p. 105, 



pis. vi. and vi. a. 

 MivART, St. George. On the Axial Skeleton of the Struthio- 



nidse. Trans. Zool. Soc. x. p. 1 (1877). 

 MosENTHAL, J. DE, and Harting, J. E. Ostriches and Ostrich 



Farming. 8vo. Londi n, 1877. 

 ScLATER, P. L. Note on JR. macrorhyncha. P. Z. S. 1877, 



p. 160. 

 Gadow, H. Versuch einer vergleichenden Anatomic des Ver- 



dauungs-Systemes der Vogel. Jenaischc Zeitschrift, xiii. 



pp. 92, 339(1878). 



