384 C. H. TURNER 



point where the air struck the dish. There, facing the current 

 they would pause with outstretched wings. Sometimes two or 

 three would be in a row. Either a sudden stopping of the cur- 

 rent or increasing the temperature to forty degrees centigrade 

 would cause them to disperse. 



Kincaid (69) finds that the color of the environment of the 

 larva has a pronounced effect upon the color of both larva and 

 pupa of the thistle butterfly. Caterpillars of this species were 

 placed in boxes of the following colors; pearl gray, lavender, 

 crushed apricot, blue, pink, green and black. The larvae placed 

 in the gray boxes became light gray. Those in the black boxes 

 became black and formed black chrysalids with a sprinkling of 

 gold. Those in the green boxes turned black; but their chrysa- 

 lids were dark brown. Those in the blue boxes acquired brown 

 bodies with bluish spines and their chrysalids were brown with 

 gold spots. Those confined to the lavender and to the pink boxes 

 developed stripes about the color of the boxes; but the chry- 

 salids of the first were light tan with gold spots and those of the 

 latter almost all gold. Those in the apricot boxes evolved 

 stripes and spines that matched perfectly the color of the box 

 and the chrysalids were the exact color of the box, with two rows 

 of gold spots. The adults did not seem to be affected at all by 

 the color of the environment of the larvae. 



OLFACTORY SENSATIONS 



Small drops of coal oil and of ammonium were placed on the 

 upper edge of an aquarium containing water-striders. When 

 the insects approached these substances, they waved their 

 antennae and dropped into the water. These reactions caused 

 Essenberg (34) to predicate a sense of smell to water-striders. 



To test the olfactory sense of beetles, Mclndoo (85) isolated 

 them in small triangular boxes with netting bottoms. He used 

 434 individuals belonging to eleven species and eight families. 

 From some he removed the antennae; from others, the elytra; 

 from others, the wings; from others, one or more legs. ' Four 

 unmutilated species responded to odors more slowly than did 

 members of the same species with amputated antennae. . . . 

 Five species without antennae responded to odors as promptly 

 as did the same species unmutilated. . . . Two species without 

 antennae responded to odors more slowly than did the same 



