Experiments with other Mammals 107 
known remained practically unexplained. By the aid of the 
Mendelian principles we are able to see at once that there are at 
least four pairs of distinct characters concerned in the offspring 
of the second generation, each pair being inherited independently 
of the other; namely, short hair versus long hair, pigmented coat 
versus albino, gray versus black coat, uniform versus marked 
coat. Hurst takes up these four pairs of contrasting characters 
and deals with them separately. 
Short Hair versus Long Hair.—The short hair of the Belgian 
breed rarely exceeds one inch, while the long hair of the Angora 
breed may exceed six inches. The first hybrids had short hair, 
the influence of the Angora not being apparent. A careful ex- 
amination, however, revealed what appeared to be faint traces 
of the Angora influence in both length and texture. The hairs 
of the hybrid coat were slightly longer, seemed softer to the touch, 
and were apparently more densely distributed than in the pure 
short coat. These traces of Angora influence are slight and 
might easily be overlooked. 
When these short-coated hybrids (7) were inbred, there were 
produced 171 young, of which 70 reached the age of two months 
or more, when the character of the hair becomes manifest. Of 
these 53 were short- and 17 long-haired. This is a close ap- 
proximation to the Mendelian expectation of 51 to 17. The 
short hair was like that of the grandparent, the long hair like 
that of the other grandparent. When the long-haired Angoras 
were bred together they produced in the next generation only 
Angoras. The short-coated individuals mated together gave 
both short-haired and Angoras in Mendelian proportions. 
Pigmented Coat versus Albino.—The cross gave in one case 
26 totally pigmented individuals; in another case the fore-feet 
showed some white markings, which Hurst thinks is not due 
to the albino influence, but to Dutch marking latent in the 
albinos. The hybrids, when inbred, produced 132 pigmented 
and 39 albinos, the Mendelian expectation being 129 : 43. 
1 In the marked coat there is white on the ends of the feet and the tip of the 
nose. ‘The Dutch is an extreme form of this marking. 
