1905.] OSTEOLOGY OF THE EURYL.EMID.E, 49 



metacarpal III. In the Euiylasmidfe this spur is, however, much 

 lai'ger than in the Coraciiform genera referred to. 



The humerus only is pneumatic ; and is subequal to, or shorter 

 than, the manus. The foi'earm is the longest segment of the limb. 

 The sulcus transversum or coraco- humeral groove is shallow. The 

 crista siqierior is triangular in form. 



The incisura ccqntis is fairly sharply defined ; the fossa 

 suhtrochanterica is lai"ge. There is a small ectepicondylar process, 

 which, it is to be noted, is not forked as in the higher Passeres ; 

 the entepicondylar process is still smaller. Yentrad of the 

 tuberculum ulnare is a prominent spur-like blunt-pointed tubei'cle 

 directed backwards and outwards so as to intei'lock with the 

 olecranon process of the ulna in the extended wing. 



On the palmai- surface immediately above the radial condyle is 

 a small tubercle for the attachment of the inner head of the 

 extensor rtxetacarpi ulnaris. 



The ulna has a prominent, pointed, olecranon process, and bears 

 a row of small tubercles, for the attachment of the secondary 

 remiges, along its postaxial border. 



The radius is slender and slightly bowed. The forearm is the 

 longest segment of the wing. 



The manus is well develojDed. As in the Oapitonidse and the 

 normal Passeres, the base of Mc. II. sends backwards a bony 

 plate to overlap? and fuse with the base of Mc. III. In the 

 Eurylfemida? this plate (intermetacarpal plate) is of considerable 

 size, its base extending down the shaft-for some distance. 



In some Coracise, e. g. Euri/stomus, there is also an intermeta- 

 carpal plate, but feebly developed, and not fused with Mc. III. 



ix. The Pelvic Limb. 



The pelvic limb, in the Euryltemida?, has, in common with the 

 Cotingidse, a syndactyle pes ; and in this respect these two families 

 resemble many of the Coraciiform es. None of the bones are 

 pneumatic ; in which respect the Eurylsemidee differ from the 

 Cotingidte, which have a pnevimatic femur, and resemble many of 

 the Ooraciidfe. 



The femur is long and slender. The popliteal fossa is represented 

 only by a shallow depression. 



The tibio-tarsus has moderately well-developed ecto- and ento- 

 cnemial crests and a long fibular crest. The shaft is curved first 

 forwards, then inwards, so that the distal end thereof is mai-kedly 

 inflected. The extensor bridge is ossified. The intercondylar 

 gorge is deep. The fibula extends to below the level of the middle 

 of the shaft of the tibio-tarsus. 



The tar so- metatarsus is moderately long. The hypotarsus is 

 complex. The distal end of the shaft is flattened from before 

 backwai'ds, and laterally expanded to form the condyle for digits 

 II.--IY. These condyles all extend forwards to practically the 

 same level, the middle condyle scarcely projecting beyond the level 



Proc. Zool. See— 1905, Vol. II. No. lY 4 



