156 CHARLES B. STOCKARD AND A. L. JOHNSON 



COMPARISONS OF LINEAR MEASUREMENTS MADE ON A GROUP OF 



SEVENTY ADULT DOG SKULLS INCLUDING VARIOUS BREEDS 



FROM THE LARGE ST. BERNARDS AND GREAT DANES TO 



THE SMALL PEKINGESE AND TOY DOGS 



These measurements were a necessary initial step in our 

 attempt to determine for the seventy individuals representing 

 the various breeds those skull dimensions showing similarity 

 or uniformity as contrasted with those showing significant 

 differences. In the accompanying charts a series of compari- 

 sons between given measurements and a number of other 

 dimensions is made. On the basis of a given computation, 

 the skulls were arranged in sequence from greatest to small- 

 est, and the same sequence then followed in charting other 

 dimensions for the same skulls. This method will be readily 

 appreciated by proceeding at once with our first series. 



All measurements in these studies were made with the best 

 calipers obtainable, accurately calibrated for anthropological 

 use. 



Zygomatic widths compared with other skull ividths. The 

 distance between the widest lateral points of the zygomatic 

 arch (pi. 35, fig. 1, F) was used in arranging a selected group 

 of skulls from seventy dogs of different breeds, the sequence 

 being from greatest to least zygomatic width. The group of 

 skulls included those from various breeds and types, from 

 great Dane and St. Bernard giants to Pekingese and dwarfs, 

 as well as from dogs with bulldog-like distortions. Text- 

 figures 2 to 10 indicate the skull measurements. Each line in 

 the several charts represents a dimension on one skull and 

 the sequence of the skulls is the same in all charts. 



The zygomatic widths (text-fig. 2) form a quite regularly 

 graded series and range from a high of 140 mm to a low 

 of only 72 mm, the broadest skull being twice the width of 

 the narrowest. Is this due only to the fact that some of the 

 skulls in the group are large and some are small? Or does 

 the zygomatic arch form a wider lateral curve in some skull 

 types than in others of the same general size? If the latter 



