OBSERVATIONAL LESSON XXIII 



55 



During the days that follow, keep an eye upon the silkworm eggs, 

 which should be placed in a small box to which air is admitted by 

 means of pin holes. If pos- 

 sible, the hatching of the eggs 

 should be seen, and when this 

 has taken place young leaves 

 of the mulberry (or, if this is 

 not possible, those of the 

 lettuce) should be put within 

 the reach of the tiny cater- 

 pillars. After the young in- 

 sects have crawled on to the 

 leaves the latter should be 

 placed in open trays. Fresh 



FIGURE 179. Silkworm Eggs. 



leaves to replace those which are eaten or become faded must be 

 provided from day to day. 



