1922.] 



Science and the Farmer. 



221 



in young heifers, into the factors controlling the formation of 

 milkj and into the wastage of reproductive activity that is apt 

 to occur in such domesticated animals as pigs, sheep, and 

 rabbits. 



The Mendelian experimenters, in Cambridge in particular, 

 coniinue to give most of their attention to such types as rabbits 

 and poultry, for these are relatively inexpensive and breed 

 rapidly. When secure conclusions have been reached on the 

 phenomena of heredity in these cheaper types, they will be 

 applied to cattle and sheep. There is, of course, much know- 

 ledge already available, and it is rapidly increasing. If the 

 farmer wishes to know how to prevent the occasional recurrence 

 of red calves in his highly-pedigreed Aberdeen- Angus breed, he 

 has only to apply to the Mendelian expert, or to think out 

 Mendelism for himself. Or if the poultry-breeder wishes to 

 tell at hatching the sex of his chicks, there is no difficulty in 

 doing this when silver hens are mated with gold cocks, and in 

 several other cases. There is money here too, for the breeder 

 can kill off his unwanted cockerels at hatching, and rear double 

 the number of pullets with the same plant. It is impossible to 

 conceive of farmers not being interested in the clearly-expressed 

 indications which Mr. Wilkins gives of the breeding-researches 

 in progress in centres like Cambridge and Edinburgh, e.g.. the 

 endeavour to improve the quality of Blackface wool, or to sift 

 out coloured hairs from the fleece. 



With healthy stock there is always something doing, but sick- 

 ness blots out the sun. So we turn with expectation to the 

 section of " Agricultural Research and the Farmer," which 

 deals with animal diseases. There we find, as we knew we 

 should, that science continues to tackle the hydra-headed mon- 

 ster which seems never to accept defeat. Thus the Royal Veteri- 

 nary College in London has been experimenting with a vaccine 

 treatment of the " joint-ill " which carries off many young "oals; 

 with a serum treatment of contagious abortion in mares: and 

 with contagious inflammation of the udder in cows. Needless 

 to say. solutions are not picked up like blackberries, but the 

 point is that the days of folded hands are quite over, and tha* 

 the conquest of disease goes on. 



Just as the Aberdeen investigators of " Isle of Wight " dis- 

 ease in hive-bees recently had their reward in the discovery of 

 a trachea-blocking mite, so in regard to other parasitic diseases 

 of other and larger domesticated animals there is progress to 

 report. Thus there has been a successful clearing up of the life- 



