92 MUSEO NACIONAL DE BUENOS AIRES. 



Es de justicia haga mención de los distinguidos anatomistas in- 

 gleses, profesor Bertraní C. A. \Yindle y profesor F. G. Parsons, 

 quienes en un notable trabajo sobre la miología de los edentados\ 

 llegan casi absolutamente á las mismas conclusiones á que me con- 

 duce la osteología. 



Esta concordancia es de tal importancia, que creo útil transcri- 

 bir la parte final de la memoria de los mencionados autores que 

 contiene las conclusiones á que llegan, con tanta mayor razón 

 cuanto parece que el mencionado trabajo ha pasado desapercibido 

 á los autores posteriores que se han ocupado de la taxonomía de 

 los edentados. 



«We have now to consider what lessons my be learnt concer- 

 ning the relations and systematic position of the anima,ls included 

 in the order of the Edentata from the study of the muscles.» 



«Flower (Proc. Zool. Soc. 1882, p. 358), in a paper on the mu- 

 tual affinities of the animáis composing this order, says tat '-the 

 two Oíd -World forms Manidae and Orycteropidae are so essen- 

 tially distinct from all the American families, that it my even by 

 considered doubtf ul whether the}'- are derived from the same pri- 

 mary branch of mammals, or whether they may no be offsets from 

 some other branch, the remaining members of wich have been lost 

 to knowledge". In using the muscles in the endeavour to deal with 

 this problem, the first consideration necessary is to ascertain whe- 

 ther there are any departures from the generalizad arrangement of 

 mammalian muscles which are common to all the families of this so- 

 called order, f or, if such exist, they are not likel}'- to be adaptations 

 to similar conditious of life in animáis far removed in relationship. 

 For instance, if similar wanderings from the generalized mamma- 

 lian arrangement of muscles can be found in the Pangolin and the 

 Sloth, these wanderings are more likel}' to be the result of kinsliip 

 than of an adaptive modification to meet similar conditions of life, 

 for few animáis more dissimilar in their habits could be imagined 

 than these two. Everyone who has worked at Edentate myolog}- 

 will at once think of two curious muscular modifications which 

 are no usually found elsewhere amongst the Mammalia, namely, 

 the rectus thoracis lateralis and tho femoral head of the flexor 

 cruris lateralis, or biceps. Both these muscles are present in the 

 two families. althouo-h, so far as we know. the rectus thoracis la- 



' On the Myolojij of fhe Edentata by, Bertkam C. A. Windle and F. G. Paksons, 

 en Froceedinijs of the Zoolojiral Sjciefy of London, a. 1899, p. 314 á 339, y 990 á 1017. 



