1912] The Ottawa Naturalist. 145 



Frequently a number of primary -tunnels, cut by 

 different females, radiate from a common "nuptial-chamber" 

 situated just beneath the common entrance-hole. In such 

 cases, with some species, the male cuts the entrance-hole, the 

 nuptial-chamber and often the beginnings of three or four 

 primary-tunnels. The male is then joined by one or more females, 

 which finish the primary -tunnels and the egg-niches ; the work 

 of the male, after the entrance of the females, consists mainly in 

 removing the chips and refuse and guarding the entrance-hole, 

 as already mentioned. 



When the primary -tunnel is long, as is the case, e.g., with 

 several species of Ips and Dendroctonus, there may be one or 

 more "ventilation holes" through the bark. 



Before egg-laying begins, whether for the first or second 

 time, the beetles cut "food-tunnels," either beneath the bark 

 of the host -tree or in the bark of twigs or trunk of other trees. 

 Many species cut their food-tunnels as continuations of the 

 larval galleries, and hibernate therein. 



In Eastern Canada most Ipidae hibernate as adults, though 

 with many species larva? and pupae also occur beneath the bark 

 in the winter. 



(To be continued). 



ACCESSIONS TO CANADIAN BOTANY I. 



By Edward L. Greene. 



There is before me a small collection of plants which, 

 although in quite too fragmentary specimens, is more than 

 ordinarily interesting in view of the locality from which it has 

 come, namely, a part of extreme north-western Yukon, not far 

 below the Arctic circle, and a region not before touched by any 

 collector. In the interior of the Alaskan peninsula there is 

 a great empire of territory somewhat elevated, and extending 

 far on both sides of the international boundary, which is almost 

 unexplored botanically, and which promises many revelations 

 to the student of plant geography. Many years ago there was 

 submitted to me a small collection from the Porcupine River 

 region, a good part of which showed a flora distinct enough from 

 that of the coastal districts of Alaska, and as totally unlike 

 that of the farther interior south-eastward. 



The fragments now at hand from the Canadian side of the 

 boundary, collected in the summer of 1911, by Mr. D. D. Cairnes, 

 have intensified the desire for a more careful investigation 



