1901. J ATSUTOMY OF GRUIFOR-Nr m^DS. 655 



Conclusions. 



The most salient generalizatioa that may be drawn from the 

 series of facts described in this paper is that, if one of the G-rui- 

 forraes shows the eutaxic or apocentric arrangement of the wing, 

 it is more likely also to show apocentric conditions of the other 

 structures examined. Of the apocentric modifications discussed 

 (and I discussed each that came within the range of my investi- 

 gations), there is none found in a diastataxic bird that does not 

 occur also in eutaxic forms. The archecentric or primitive condi- 

 tions similarly are more abundant in the birds which show the 

 archecentric or diastataxic condition of the wings. Apart from 

 this general correlation of apocentricities, however, thei'e is not 

 the same close and definite incidence of modifications among the 

 Gruiformes that there is to be found in the Alcedinidse and 

 Columbidfe. I hope in later communications to extend these 

 observations to a number of forms allied with the Gruiformes, and 

 for the present I wish to reserve more detailed conclusions and 

 especially the intei-pretation of the series of facts in terms of 

 taxonomy. 



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43* 



