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CHARLES E. STOCKARD AND A. L. JOHNSON 



ments. While adjacent skulls may differ only slightly in 

 bregma to nasion lengths, the lengths of the floor of the 

 anterior nares may show wide variations. The existence of 

 such pronounced disagreements makes it evident that the 

 appearance of a general accord between the two figures is 

 more largely due to a gradation in size of the skulls than 

 to differences in skull type. 



/O 



Text-figure 47. Sequence M. Anterior end of internasal suture to anterior 

 tip of the superior dental alveolus. Same skull sequence as text-figure 45. 



Finally, text-figure 48 represents measurements of posterior 

 cranial length, from bregma to supraoccipital spine (pi. 35, 

 fig. 3, B-C), for comparison with the anterior cranial meas- 

 urements from bregma to nasion. The range of measurements 

 from bregma to the supraoccipital crest is from 80 mm down 

 to 36 mm, or as 2.2 :1. This range is not quite so great as 

 the one for anterior cranial length, and there is practically 

 no accord between the slope formed by the tops of lines 

 representing bregma to nasion lengths (text-fig. 45) and the 

 very irregular series for the measurement from bregma to 

 supraoccipital spine (text-fig. 48). 



These charts of mid-dorsal measurements indicate that 

 in the different typed dog skulls there is little correlation 



