14 N. H. AGR. EXPERIMENT STATION. iBulletm 160 



When a male offspring is born, the proper combination may 

 occur to give him a simplex horn, which will be a short stub 

 or scur. Such a ewe, bred upon a pure hornless ram, would 

 theoretically produce fifty per cent, of her male lambs with 

 scurs and fifty per cent, without horns. These circumstances 

 are occurring constantly in Down flocks. I remember vividly 

 when I was a boy on the farm that one year we used as sire 

 an imported Oxford Down ram on our selected registered 

 Oxford Down ewes. Forty-two males lambs were sired by him. 

 Of these two had large horns, eighteen scurs and the rest hornless. 

 It was discovered subsequently that the ram normally possessed 

 scurs or short horns, but these had been destroyed early in life 

 by caustic potash, so that at the time we purchased him they were 

 not noticeable. The ram was evidently simplex in respect to 

 horns, and the two lambs with large horns were doubtless duplex, 

 or possessed two horn determiners, being the issue from simplex 

 ewes. I also remember, and have received corroboration by 

 my father, that the same year a ewe lamb produced a sturdy 

 growth of horn, Avhich while young (for she was killed early) 

 gave pretensions to become as long as the horn of a Dorset ewe. 

 This, again represents the condition of a duplex horn. The 

 breeders of hornless sheep are never free, except by judicious 

 selection of strains that assuredly never produce horns, from the 

 frequent reappearances of horn growths. In the various fami- 

 lies of the Merino the opposite condition obtains. The horn of 

 the males is most variable in size and at times disappears. The 

 reason is obvious: the duplex condition is at times, or in some 

 strains, broken down into the simplex, and, when two simplex 

 horned sheep are bred together, twenty-five per cent, of the 

 rams theoretically may be hornless. 



Let us now consider our data and methods of obtaining these. 

 In studying horns we first found it necessary to select some com- 

 mon standard whereby we could describe and compare accu- 

 rately all sizes and degrees of horns. The ratio of circumference 

 to length was taken for this purpose. This is attained in the 

 following manner: Two measurements of length are made from 

 the poll to the tip of the horn, one on the inside and the other on 

 the outside of the horn. An average of these is taken and the 

 results represent the length of the horn. The circumference is 

 taken as close to the poll as possible. Any horn having a ratio 

 less than 1.00, we have designated a scur and beyond that short, 

 medium or long horn as the ratio justifies. 



The first problem that presented itself was the effect or rela- 

 tion of age to the ratio; or, in other words, whether the ratio 

 was constant at all ages. Without definite knowledge in this 

 regard many errors might easily enter that would greatly depre- 

 ciate the scientific value of the data. To this end measurements 



