10 GRAMMAR OF ENTOMOLOGY. 



north and east winds ; but plenty of air in warm 

 weather is beneficial. The leaves should be given 

 to them perfectly dry ; if brought from a distance, 

 they preserve their freshness for many days in a 

 tin box, or on the cold bricks or stones of a cellar. 



25. After the fourth change, the silk- worms 

 require constant watching ; twice a day they 

 should be carefully looked over, and those ready 

 to spin picked out, and placed in little cells, made 

 of writing-paper, about as large as one's thumb, 

 open at one end, and closely screwed up at the 

 other ; their paper cells may be pinned to lines 

 crossing a room, and placed touching each other 

 on the line. 



26. The period of a silk-worm being ready to 

 spin is plainly indicated by its ceasing to eat, and 

 becoming suddenly more transparent and of a yellow 

 colour ; it will also begin to spin a few threads of 

 silk among the leaves, or in a corner of the tray. 



27. The silk-worm, when placed in the cell, 

 spins a few loose connecting threads, attached to 

 every side of the cell : it then forms a regular 

 oval ball of silk, which is suspended in the centre 

 of the cell, and in the interior of which it continues 

 to work for five days. 



28. If the cells containing the spinning silk- 

 worms, are placed regularly on the line in the 

 order in which they begin spinning, then there 

 will occur no difficulty in taking them off, in the 

 succession in which they stand, as the first in 



