CONTENTS. 



Organization of the Station n 



Announcements vn 



Are swine profitable in winter? (Bulletin 269) 1 



Are sheep profitable in Maine ? (Bulletin 269) 3 



Fertilizer experiments on apple trees at Highmoor Farm (Bul- 

 letin 269) 9 



Commercial varieties of oats grown at Highmoor Farm in 1917 



(Bulletin 269) 16 



Soil test experiment at Aroostook Farm (Bulletin 269) 17 



Effect of omitting potash upon the oat crop (Bulletin 269) 31 



Effect of omitting potash upon the potato crop (Bulletin 269) . . 33 

 The potato crop in its relation to soil and fertilizer (Bulletin 269) 35 

 Potatoes grown at Aroostook Farm with different forms of ni- 

 trogen (Bulletin 269) 37 



Plant breeding at Aroostook Farm (Bulletin 269) 40 



Eastern aphids : a few species of Prociphilus (Bulletin 270).... 45 



Apple spraying experiments in 1916 and 1917 (Bulletin 271).... 102 

 Inheritance studies of color and horn characteristics (Bulletin 



272) 129 



The biology of Maine species of Altica (Bulletin 273) 149 



Report of progress on animal husbandry investigations in 1918 



(Bulletin 274) 205 



Abstracts of publications in 1918 not included in bulletins or of- 

 ficial inspections (Bulletin 275) 229 



Meteorology (Bulletin 275) 235 



Report of the Treasurer (Bulletin 275) 237 



Index for 1918 (Bulletin 275) 241 



