180 



DWIGHT E. MINNICH 



"* [Fig. 1 Plan of apparatus as seen from above and as seen in cross-section, a, 

 rectangular pan of tin, containing cheese-cloth pack saturated with applejuice; 

 h, rectangular pan of tin containing cheese-cloth pack saturated with distilled 

 water; j, applejuice; p, Petri dish; s, wire screen; low' , wooden platform; xx' and 

 yy', wooden cross-pieces. The arrows, 1, 2, and 3, represent the positions in which 

 the butterflies were tested, the position of the walking legs being shown by the 

 cross-bars. 



