NO. 



18 



SENSE ORGANS OF COLKOPTERA — McINDOO 



snugly, and then a dark green window shade (fig. 2, A) was pulled 

 to the bottom of the window. The door (B) was made light-proof by 

 fastening slri])S of black cloth around all its edges, and its transom 



Fig. 2. — Diagram of a constant temperature and humidity dark-room, showing 

 parts of room and apparatus used in testing plioto-geotactic responses of Mexican 

 bean beetle. The parts and apparatus are as follows : A. window shade; B, door; 

 C, ventilator; D, box; E, table; F, lawn sprayer; G, garden hose; H, bath 

 towels; /, hygrothermograph ; /, thermometer; K, outlet water pipe; L, electric 

 fan; M, photo-geotactic box; A'^, water screen; O, electric lamp; P, siphon run- 

 ning to water screen ; Q, siphon running from w^ater screen ; and R, stool. 



was changed into a ventilator (C) through which air passed freely, 

 but no light! The temperature and humidity were partially controlled 

 by the following means. A box (D), 40 inches long, 24 inches wide. 



