36 N. H. Agr. Experiment Station [Bulletin 304 



lary tube is taken as a measure of the rate of penetration of the prono- 

 tum. The ultimate aim of this study is to relate speed of penetration 

 of an oil to its molecular structure or its chemical or physical proper- 

 ties. {Purnell Fund) 



Insect Record 



Particular attention was given by our entomologists this year to the 

 outbreak of the European spruce sawfly which severely defoliated 300 

 acres of spruce on the north side of Mt. Monadnock. Studies will be 

 made of the life history and control of this pest under New Hampshire 

 conditions and are already under way to determine the effects of tem- 

 perature on the hibernating larvae. 



In cooperation with the State Department of Agriculture trap logs 

 have again been placed for studies of the elm bark beetles which are 

 known to transmit the Dutch elm disease. {Hatch Fund) 



Seed Testing 



The regular seed inspection work for the State Department of Agri- 

 culture was conducted as usual. During the year. 503 samples of seed 

 were handled in the laboratory. Of this number 439 were collected by 

 the State Inspector and are reported in Bulletin 299 ; the remaining 64 

 samples were sent in by private individuals. The referee work was 

 done as usual. The work was done by Mrs. Bessie G. Sanborn. Seed 

 Analyst, assisted by students. {Miscellaneous Income) 



Seed Certification 



Sixty-two acres of potatoes were entered for certification and 95.9 per 

 cent, of the acreage entered passed final inspection. {Miscellaneous 

 Income) 



Calves Should be Vaccinated Young 



Vaccination of calves as a means of control of Bang's Disease 

 should take place before the animals are six months of age, finds C. L. 

 Martin. Inoculations were given 21 cattle varying in age from four 

 years to four months. Five head were between four and six months 

 of age, and these five were the only ones to react negatively when tests 

 were made within a year of inoculation. Since at the present time stock 

 sold for breeding purposes or milk production must be negative to the 

 blood test, the inoculation of older animals would appear to be inad- 

 visable. {Purnell Fund) 



Technique for the Eradication of Pullorum 



Studies on cases of non-specific reactors encountered during rou- 

 tine testing of blood samples for Pullorum have been made by C. A. 

 Bottorff to determine if other salmonella organisms were responsible. 



In no case were any salmonella organisms found other than S. 

 pullorum. The liver, ovaries, spleen, heart, and any pathological lesions 

 found were cultured. 



There were 176 birds from 79 fiocks examined in this study. Of 

 these, 134 birds from 68 fiocks were classed as negative because Sal. 



