Shukki.ih' : ( )sri:()i,OGY oK thk Hekodiones. 225 



ing the shallow concavity there formed into two nearly equal fosste. 

 Transversely, the head of this bone is wider than the distal end of the 

 index shaft of the carj)o-metacari)us which articulates with it. Afrdins 

 i/i\'i/ l)resents nothing peculiar; it has the usual small ])rocess like ele- 

 vation upon its hinder border, and when articulated /// s/V// is closely 

 pressed for nearly its entire length against the first joint of the index 

 finger. The trihedral terminal phalanges of pollex and index digits 

 are much alike in their morphology, and depart in no striking charac- 

 ter from what we see in those bones in all large ordinary birds. Small 

 free sesamoidal bones seem to be absent from about any of the articu- 

 lations of this arm-skeleton of Tantalus. 



In the matter of development x\\& pelvic limb is ecpial to the pectoral 

 extremity, but the relative proportions of the corresponding bones of 

 the three first segments is cpiite different. For instance, the femur 

 has a length of 10.3 cm., while the tibio-tarsus is 26.5 cm. long, 

 and the tarso-metatarsus measures 21. i centimeters. Of course, in 

 this, the fingers and toes do not enter into a comparison, and we 

 would simply add that the mid-anterior toe has a length of about 10.7 

 cm. The basal phalanx of the outside toe is the longest of all the 

 joints of pes, measuring 5 cm. ; that of the middle toe being 4.2 cm. 

 and of the inside one 4.4 cm. The free first metatarsal bone is 2 

 cm. long, and the basal joint of hallux has a length of 4.0 centi- 

 meters. 



As in the case of the humerus of the arm, \.\\q. fenitir is highly pneu- 

 matic, none of the other bones of this limb enjoying that property. A 

 large, single pneumatic foramen, subelliptical in outline, is found on 

 its anterior aspect near the summit, and just in front of the trochanter. 

 Other minute ones occur in the rotular channel between the condylar 

 crests. This bone is quite straight with smooth cylindrical shaft upon 

 which the usual muscular lines are but faintly marked. Antero-pos- 

 teriorly, the great trochanter is of considerable width, and its crest 

 rises conspicuously above the smooth articular summit of the shaft. 

 The large, globular and sessile caput femoris exhibits on its upper sur- 

 face a vvell-circuniscribed pit for the insertion of the round ligament. 

 At its distal extremity we are to note the unusual depth of the rotular 

 channel in front, giving, as it does, great prominence to the condyles 

 in that region. These last are of themselves large, with their lower- 

 most points being very nearly in the same horizontal plane. Poste- 

 riorly, the external condyle is powerfully developed and very prom- 



