AMEGHIXO: EL ARCO ESCAPULAR DE LOS EDENTADOS. 5 



der of tlie coraco-scapiüar foramen, and being continued from 

 tlie lower edge of the latter to tlie free lower margin of the com- 

 pound bone. I bave also observed the coracoidal element ¡Derfectly 

 distinct in tbe skeleton of an immature Slotb in the Museiim. » 



« The large size and the distinctness of the coracoidal element 

 in the pectoral girdle of 

 the Sloth appear to me 

 afford considerable sup- 

 port to the view that the 

 Edentates form a group 

 of equal valué with the 

 typical Eiitheria. » 



« The interest of the 

 specimen does not, ho- 

 ■^ever, cease here. If the 

 figure of the pectoral 

 girdle of the Sloth be 

 compared with that of 

 the reptilian Dicynodon 

 (fig. 2), it will be ap]3a- 

 rent that the elements 

 marked c in bot are ho- 

 mologous; each articula- 

 ting with the lower bor- 

 der of the front of the 

 scapula, from Trhich they 

 are partially separated 

 by a foramen (f), and 



each entering into the 

 „ . „ , , . , Fig. 2. Dicynodon. Omoplato derecho: se, esca- 



formation of the glenoid ^^^^^. ^^ acromion; c, coracoideo; A foramen co- 

 cavity. Xow m the Dicy- raco-escapular; ^í, cavidad glenoides; «¡c, meta- 

 nodont the bone marked oracoideo. 

 c as nsually been identi- 



fied with the precoracoid. According, however, to Professor Ho- 

 wes ^ the latter term shoulcl be restricted to a portion of the clavi- 

 cular arch, aucl the ñame epicoracoid applied to the element 

 under consideration. This emendation, if properly authenticated, 

 I should of course have been willing to accept, had it no been for 

 another consideration. Apart from that consideration, we must 



onc 



1 Journ. Anat. Fhys., vol. xxvi, p. 403 (1893). 



