4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I49 



represent a juvenile bird. Lambrecht's photograph (p. 319) is not 

 clear, but the tibiotarsus represented shows general resemblance to 

 that of Dissoarodes milleri. The latter appears to have a more mas- 

 sive shaft, a more pronounced internal ligamental prominence, and 

 an oval rather than round distal opening of the tendinal groove, when 

 compared with the tibiotarsus illustrated by Lambrecht. These dif- 

 ferences, the question of identity and age of Propelargus tibiotarsi, 

 and occurrence of that genus in French Oligocene to Miocene deposits, 

 seem to preclude its congeneric relationship with D. milleri. 



The other fossil storks not previously discussed are not represented 

 by tibiotarsi, except for certain species of Recent genera which will be 

 discussed below. Palaeopelargus nobilis (De Vis, 1891) was described 

 from metacarpal fragments and appears much larger than D. milleri 

 (larger even than X enorhynchus) . Prociconia lydekkeri, from Pleis- 

 tocene cave deposits in Brazil, is based on distal tarsometatarsi. It 

 appears to represent a species the size of Leptoptilos (sp.), but little 

 can be said about its affinities until we learn more about it. Pelargo- 

 pappus is comprised of three species from the Oligocene (possibly 

 also Eocene) and Miocene of France, and the material includes no 

 tibiotarsi, except for a proximal tibiotarsus of P. magnus. The species 

 of Pelargopappas were the size of Cinonia ciconia (P. magnus) or 

 smaller. According to Lydekker (1891, p. 68) Pelargopappus magnus 

 shows similarities to Ibis. Palaeoephippiorhynchus dietrichi, an Oligo- 

 cene stork from North Africa, is not represented by tibiotarsal 

 material. It is apparently closely related to Ephippiorhynchus (Lam- 

 brecht, 1933, pp. 325-326), a stork approximating species of Leptop- 

 tilos in size (see discussion of modern forms below). Ciconiopsis 

 antarctica was an Argentine Oligocene form and is known only 

 from a metacarpus. Kretzoi (1962) has recently described Pelar- 

 gosteon tothi from the Pleistocene of Rumania. This form was 

 between Ciconia (sp.) and Leptoptilos (sp.) in size, but no tibiotarsal 

 material is yet available from it. 



The tibiotarsus of Dissourodes milleri appears to differ considerably 

 from fossil storks represented by tibiotarsal material. Perhaps the 

 greatest need in paleoornithology is for comparative osteological 

 studies of modern (and fossil) species, with emphasis on correlating 

 modifications of elements within individual structural complexes and 

 among related structural complexes. Such studies are essential to 

 enable some evaluation of the biology of fossil forms, as well as to 

 enable us better to establish their relationships. The differences 

 between the fossil form and other represented tibiotarsal material 



