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Show 26 PROF. B. C. A. WINDLE AND MR. J. HUMPHREYS [Jan. 14, these is doubtless true also in lesser degree of the greater number of specimens coming under examination. It thus becomes apparently a hopeless task to look for evidence as to the proximate or ultimate derivation of the breeds of domestic dogs in their skulls or teeth. Some points of interest may, however, be learnt from a comparison of certain of the measurements, and with these we now proceed to deal in order. Relative Breadth and Length of Skulls and Palates. In the tables next to follow we have endeavoured to classify the skulls according to their relative breadth and length and according to that of their palates. An index has in each case been taken by using the formula Width X 100 Length In the first instance this has been applied to the measurements " total length" and "zygomatic width." Those dogs of which the index is above the average are those possessed of short, broad heads, whilst those below are in varying degrees long and narrow-headed. A distinct group placed near to but slightly below the average, may be'looked upon as occupying a medium position between the two extremes. The second column, which has been placed side by side with the first for the sake of more easy comparison, deals with the relative size of the palatine surface. The first column, whilst conveying a good idea of the relative length and breadth as they appear in the living animal, conveys at the same time a somewhat incorrect idea of the actual condition, since it is dependent upon the amount of projection of the zygoma, which is obviously a more or less variable factor. A comparison of the two columns shows how much some skulls owe their apparent breadth to zygomatic projection. It also shows that the broadest and narrowest heads fall into nearly the same positions in both columns, those intermediate between the two extremes showing greater discrepancies. Some of the figures are from the measurements of single specimens ; in cases where more than one has been examined the measurements are averages. It will be noticed that the distinctly broad-headed dogs form a well-marked group by themselves, including tbe Chinese Pug-nosed Spaniel, the Pug, Bull-dog, Black-and-tan Toy Terrier, and King Charles' Spaniel, a considerable interval existing between these and the next. All these, it will be noticed, are highly artificial breeds which require great care and attention to be bestowed upon them to prevent deterioration with its consequent elongation. Next to this group comes one largely consisting of Terriers with heads inclining to be broad. A miscellaneous group next follows gradually decreasing to the distinctly narrow-headed dogs such as the Irish Wolf-dog and the Greyhound. It is interesting to notice the |