16 N. H. AGR. EXPERIMENT STATION [Bulletin 212 



As the work developed, one locality was found where larvae could be ob- 

 served and material secured under field conditions. This material was carried 

 through separately from that described above and a start was made toward 

 securing data on specimens that had originated under New Hampshire condi- 

 tions. Carefiil and detailed observations were begun on the habits of the adults. 



Three specimens of parasites were secured. Two of these were bred from 

 pupae collected August 13 and August 23, on a farm at Stratham, X. H. One 

 was bred from a larva from among the material brought from Massachusetts. 



Sheep Breeding. 



The flock developed from Southdown and Rambouillet parentage has now 

 been cut down to 25 head; and while some further culling and selection will bo 

 necessary to perfect a uniform standard of appearance, it is the intention of 

 E. G. Ritzman (Animal Husbandry), who has this work in charge, to maintain 

 the flock at approximately this number. As an economic asset this new com- 

 bination holds out good promise, since their average fleece weighed 83 pounds, 

 graded as one-half blood staple and sold for top market price, while the male 

 lambs of this cross (unselected) at 15 weeks of age averaged 67 pounds and 

 sold for somewhat over nine dollars per head. 



The first crop of Fi has been obtained from the Rambouillet-Oxford ci'oss. 

 This cross will be used as a basis for developing the highly important economic 

 traits of twinning and higher milk yielding capacity, which are, of course, the 

 fundamentals essential to profitable lamb production for early markets. 



As a great asset to the furtherance of this end one ram and five ewes have 

 been obtained from the estate of Dr. Alexander Graham Bell, whose persistent 

 efforts after 33 years of inbreeding have resulted in a breed of sheep possessing 

 from four to six functional nipples and a relatively high degree of fecundity. 

 It is hoped finally to transmit these two valuable characteristics on the flock 

 originated here, thus finally combining reasonably good mutton conformation 

 and high-grade wooi-with the factors that determine a profitable lamb crop. 



A treatise on the inheritance of size and conformation in sheep has been 

 issued this year as Technical Bulletin No. 25, and the material is being assem- 

 bled for another on the inheritance of wool. After the technical p"hase has thus 

 been covered on the inheritance of size, conformation, and wool, it is planned 

 to prepare the results for publication in more popular form. 



Nutrition Studies. 



Results obtained during the first two years, suggesting a rather remarkable 

 seasonal variation in heat metabolism on a constant feed level, was the cause 

 of devoting the entire attention during the past year to the influence of environ- 

 mental temperature. 



This variation in heat metabolism on constant rations was rather unexpected. 

 The uniform general drop in heat metabolized during the coldest part of the 

 winter of 1918-1919 not only indicated a marked seasonal variation, but quite 

 contrary to previous investigations on this subject the energy metabohsm was 

 lowest during the colder weather. This year's work was, therefore, planned to 

 determine the influence of the environmental temperature both in the metab- 

 olism stalls and in the respiration chamber, allowing temperatiu-e as the only 

 variable; feed, water, and general care remained as nearly identical as possible. 



