76 Kansas Academy of Science. 



of the cover and a glass tumbler or wide-mouthed bottle was placed in 

 an inverted position over the opening. The latter barrier was provided 

 as a trap for the retention of adult insects when they attempted to 

 leave their quarters. These provisions readily facilitated the carrying 

 on of regular observations upon the behavior of the various pests and 

 their parasites so far as the forms appeared in any product held within 

 the chamber. From time to time, the relative abundance and ap- 

 proximate increase or decrease in numbers of a given species in similar 

 or different sorts of stock could be noted almost at a glance. 



BREEDING IN ISOLATION. 



After some deliberation regarding the procedure by which the sev- 

 eral kinds of insects could be successfully bred in isolation, the follow- 

 ing measures were devised and employed as offering the best advantages 

 in harmony with storage conditions. They allowed observations to be 

 taken day by day on the developmental phases of any form, whether kept 

 in dark or exposed to light. The perfect determination of life histories 

 depended on the breeding of each species in all of the diverse classes of 

 stock that happened to be found infested by the particular insect. 

 An equalization of other factors was secured by uniform manipulation 

 so far as it proved to be practical for obtaining adequate results. 



In the selection of specimens, the adults were preferred for starting 

 a series comprising a number of individuals in a test. When the sexes 

 could not be readily distinguished a few mature forms of a kind were 

 confined together. Otherwise, when possible, active or mated pairs 

 were chosen for the initiative step. 



Small tin boxes were utilized for installing some confinements. In 

 most cases, however, the isolations were made in tubular glass vials 

 measuring not less than four inches in length and three-fourths of an 

 inch in diameter. Each vial was provided with a stopper of special 

 construction, designed with the object of allowing atmospheric changes 

 to take effect within the tube in accord with the weather, and at the 

 same time preventing escape of the inclosed insects. These provisions 

 required only a simple device consisting of a tight-fitting cork, through 

 the middle of which a vent of three-eighths of an inch aperture had been 

 punched, the opening then being covered with a disk of fine brass gauze 

 that was attached securely over the inner face of the stopper by means 

 of small pins. By making the insertions at equal distances apart on the 

 rim, no more than four pins were needed for holding the disk tight to 

 the plug. The gauze when properly affixed and trimmed evenly around 

 the circumference protected the cork from being gnawed or burrowed. 

 Such damage was frequently committed by cadelle beetles whenever any 

 portion of the stopper happened to be exposed within the tube con- 

 taining these insects. 



In order to obtain darkened conditions consistent with the habits of 

 secretive insects, the tubes in most instances were placed under cover 

 in pasteboard boxes and tilted so that the contained material and living 

 forms remained together in the bottom of each inclosed space. For 

 comparative purposes, specimens were occasionally left in full reach 

 of diffused sunlight. 



