no. 9 



A NEW PLIOCENE STORK — SHORT 



Miocene 

 Propelargus 

 olseni — Florida 



Pliocene 

 LeptOptilos 

 pliocenicus — Russia 



Pleistocene 



Xenorhynchopsis minor — 

 Australia 



Leptoptilos titan — Java 



Mycteria wetmorei — U. S. 



Pelargosteon tothi — 

 Rumania 



Palaeopelargus nobilis — 

 Australia 



Prociconia lydekkeri — 

 Brazil 



The fossil will be compared below with Ibis, Leptoptilos, Ciconia 

 and Mycteria. Amphipelargus major (Lydekker, 1891) of the Lower 

 Pliocene from the island of Samos is larger than the present fossil 

 species, and has markedly different tibiotarsal features. Its distal 

 articulating surface projects laterally due to expansion of the anterior 

 inner condyle. This results also in a much wider intercondylar groove 

 than in Dissourodes milleri, which shows no notable lateral expan- 

 sion. The latter also exhibits a much broader supratendinal bridge 

 and an oval, rather than round, distal tendinal groove opening. 

 Amphipelargus too differs from Dissourodes in possessing a deeper 

 posterior intercondylar sulcus. 



Xenorhynchopsis of the Australian Pleistocene (De Vis, 1906) 

 differs from Dissourodes in the proportionally greater width of the 

 distal end of the tibiotarsus. The condyles are more broadly spaced 

 with a broader intercondylar groove than in Dissourodes. The distal 

 opening for the tendinal groove is round and not oval, as in the 

 present species. The major feature of Xenorhynchopsis is the pres- 

 ence of a small subpyriform projection at the base of the tubercle 

 lying between the condyles at the distal end of the supratendinal 

 bridge. Unfortunately, the tubercle is broken off near its base in 

 the fossil Nebraska tibiotarsus, but other differences mentioned make 

 it unlikely that Xenorhynchopsis is closely related to Dissourodes 

 milleri. 



The genus Propelargus was described by Lydekker (1891) for an 

 Oligocene (or Eocene) and a Miocene species, P. cayluxensis and P. 

 edwardsi, respectively. A tibiotarsus possibly of the latter species 

 (Lydekker, op. cit., p. 65) was not figured and the description given 

 does not permit detailed comparison with the fossil tibiotarsus. Lam- 

 brecht (1933, pp. 318-320) accumulated one complete and four partial 

 distal tibiotarsi assigned to P. edwardsi, but the complete one may 



