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to above, merits a somewhat fuller description. It is adapted for 

 the storage through the winter of pupae and other hibernating 

 insects. The room is a dark one built in one corner of the base- 

 ment. The partition separating it from the rest of the basement 

 is a double wall of matched lumber and building paper, enclosing 

 an air-space. This is rendered necessary by the high tempera- 

 ture of the basement, due to the presence in it of the heating ap- 

 paratus. There is an inlet for cold air, formed by an 8-inch tile 

 pipe extending under the foundations of the building and open- 

 ing outside. There is also an outlet for warm air, made by leav- 

 ing an opening into two of the spaces between the studding of 

 the outside wall, these spaces being furnished with another open- 

 ing through the side of the building just beneath the eaves. The 

 outlet beneath the eaves of this flue is furnished with a hinged 

 door which can be opened or shut by means of a cord ; the size 

 of the inlet for cold air in the floor of the cold-room can also be 

 varied. In these ways the temperature of the room can be kept 

 under control. The room on the ground-floor immediately above 

 the cold-room is the laboratory, and near the assistant's table 

 there is an opening covered by a pane of glass into the outlet-flue 

 of the cold-room ; in this flue, opposite the pane of glass, there 

 hangs a thermometer, by means of which the temperature of the 

 air that is escaping from the cold-room can be easily ascertained. 

 Since the establishment of our insectary an extensive series of 

 experiments in tracing out the life histories of certain insects in- 

 jurious to vegetation, and in determining the best methods of 

 checking their ravages have been carried on. Nearly two hun- 

 dred different species of insects have been studied. But the 

 greater part of the work has has been concentrated upon a lim- 

 ited number of these. Thus during the past year, although we 

 have bred a large number of species, keeping careful notes on the 

 transformation of each, more than half of the work done has been 

 devoted to experiments designed to determine the most practica- 

 ble methods of combatting wire-worms and millipedes. It has 

 seemed better to concentrate our energies as much as practicable 

 upon a few problems of first-class importance. Still the demands 

 upon us for information regarding a great variety of questions is 

 such that a limit is set to the degree in which we can specialize. 

 For this reason although, as just indicated, the chief part of our 

 experiments have been in another direction during the past year, 



