82 MILLS. [1899 



in different specimens ; tlie largest was in the middle, with a smaller 

 one on each side, and occasionally one below, making five altogether ; 

 but sometimes the lowest pair was absent ; sometimes the middle large 

 spot was not entire, conjecturally the marking differed with the age 

 of the caterpillar. On the preceding — that is, the eleventh — segment, 

 there were two clearly defined brownish spots, and along each side of 

 the caterpillar was a row of dark dots, one on each segment. 



The caterpillar was slightly sprinkled with pale hairs, or fine 

 bristles, and had such a capacity (consequently) for catching and 

 retaining a covering of flour, that I was obliged perpetually to remove 

 it with the moistened tip of a finger in order to obtain a clear view of 

 the markings. 



The chrysalis (which lay in a silken cocoon of spun- up flour) 

 showed the chief points of the form of the coming insect plainly ; the 

 colour was that of beeswax below, shading to reddish brown on the 

 back, and reddish brown also at the end of the somewhat prolonged, 

 slightly curved tail, which ended bluntly or cylindrically ; the eyes 

 were of a darker shade of red. 



I had not the opportunity of observing how long the chrysalis state 

 lasts before development of the moth, but it is stated by Prof. Zeller 

 that the time taken is three weeks. 



The rapidity of succession of generations of Ephestia is influenced by 

 temperature ; where this is favourable, as in mills working day and night, 

 it is found that there may he, five or six successive generations yearly."' 



The method of life is for the minute maggot, which is almost 

 invisible to the naked eye when it comes out of the egg, to begin 

 immediately to spin a fine glutinous silk, or web, so tenacious that 

 it adheres firmly to the smoothest surfaces, and thus the bolting 

 apparatus, woodwork, machinery — in fact, everything that the cater- 

 pillars can get at — become covered with a thick coating of whitish web, 

 with grains of flour or meal attached. As the maggot (larva) grows — 

 which it does so rapidly that in three or four days (unless the weather 

 is not too cold) it is a line in length — it remains within the sort of 

 " felt "-like web as long as food is in reach ; but when this ceases to 

 be the case, it comes out and spins a new layer of web on the top of 

 it, and this process is continued until great masses are formed of the 

 spun-together flour. In my own experiments I have seen flour felted 

 by a colony of Ephestia, which I kept under observation, into a mass 

 ten inches long by six wide and about an inch deep, this mass being 

 webbed firmly together throughout. On the broadscale and widespread 

 amount of observation which it was in the power of Mons. Danysz to 

 carry out, he mentions having seen these spongy, elastic spun-up 

 masses measure several "metres" in length. As a "metre " equals 



• See ' Ephestia kuhniella,' by J. Danysz, pp. 10-14 (referred to in note, ante, p. 80). 



