ORTHOPTERA OF INDIANA. 189 



They also seem to have a peculiar liking for paints of various kinds, 

 and in the office of the U. S. Coast and Geodetic Survey, at Washing- 

 ton, have done much damage by eating ofE the blue and red paints 

 from the drawings of important maps. Glover, loc. cit., states that in 

 his office "They made a raid on a box of water colors where they de- 

 voured the cakes of paint, vermilion, cobalt and umber alike; and 

 the only vestiges left were the excrements in the form of small pellets 

 of various colors in the bottom of the box." 



The ootheca of the Croton bug is very light brown, a little over 

 twice as long as broad, 7.5x3.5 mm., with the sides somewhat flat- 

 tened and the edges parallel. Within it the eggs, thirty-six in num- 

 ber, are arranged in the usual two rows. It is carried about by the 

 mother roach for several days with from half to three-fourths of its 

 length protruding from the abdomen, and when dropped in a favor- 

 able place the young, evidently very soon, emerge from it; for in a 

 bottle in which a female with protruding ootheca was placed at 

 eleven o'clock p. m. the young were found to have emerged on the 

 following morning at eight. They were then wholly white, except 

 the lateral edges of the abdomen, where a blackish tinge was evident. 

 By five o'clock in the afternoon of the same day, having meanwhile 

 eaten their fill of moistened wheaten bread, they had become too 

 large for their skins, and had moulted for the first time. They then 

 measured 3 mm. in length, and the head, pronotum, abdomen, and 

 apical half of antenna?, were black, while the other two thoracic rings 

 and the basal half of antennas were a grayish white. The half grown 

 young are very dark brown, with the first four or five segments bor- 

 dered with yellow, and with traces of a lighter median stripe. 



In giving a remedy for this and other roaches I can not do better 

 than to quote from Mr. Marlatt's excellent bulletin as follows: 



"Like the crows among birds, the roaches among insects are ap- 

 parently unusually well endowed with the ability to guard themselves 

 against enemies, displaying great intelligence in keeping out of 

 the way of the irate housekeeper and in avoiding food or other sub- 

 stances which have been doctored with poison for their benefit. 

 Their keenness in this direction is unquestionably the inheritance of 

 many centuries during which the hand of man has ever been raised 

 against them. 



"Fumigation. — A thorouglily efi^eetive and simple means of ridding 

 one's premises of roaches has been found, however, and is in fumigat- 

 ing with hydrocyanic-acid gas. The experience of the last year or 

 two has demonstrated that this gas, formerly employed for disinfect- 

 ing nursery stock and orchard trees (notably citrus) from scale and 



