134 



MERISTIC VARIATION. 



[part I. 



true sternal ribs (Fig. 12, II.). The measurements are given by 

 Furbringer for 7 specimens, of which those relating to two ex- 

 treme cases (here figured) are appended. 



Furbringer, M., Morph. Jahrb., 1879, v. pp. 386 and 387. 



66. By comparison of specimens of the Pigeon, Columba livia, var. 

 domestica, a similar correlation was found to occur, as shewn in 

 Fig. 13, 1, and II. (Furbringer's specimens A and E). 



XI XV Cr XW Cr XI\ r Cr XV St' 



XB XW Cr XIV Cr XV Cr 



Fig. 13. Diagrams of brachial plexus and cervical ribs in two Pigeons (C. livia, 

 var. domestica) after Furbringer. 



I. Case in which the 12th, 13th and 14th vertebrae bore cervical ribs. II. Case 

 in which the 13th, 14th and loth bore cervical ribs. Letters as in Fig. 12. 



The measurements of the ribs of these individuals were as fol- 



lows 



