3 2 The Scottish Naturalist, 



unproductive till the end of July and August, when mine had become unprofit- 

 able. It therefore depends, in some degree at least, on the locality, and each 

 one's experience should teach him what the best time is in his own neighbour- 

 hood. One thing, however, must not be forgotten, and that is, that the most 

 productive time is not always the same every year. I would recommend that 

 sugaring should be begun in March, left off during the time the sallows are in 

 bloom, resumed in May, and continued till the ivy comes into blossom in 

 October. During that time sugar should be tried at least once a week, and 

 when found productive, prosecuted with energy. 



(4) We must now consider the great question of "the weather;" upon the 

 state of which greatly depends whether our labours will be in vain or not. The 

 most favourable combination of circumstances is a S., S.W., or W. wind, not 

 too strong, nor veering from one point to another, but blowing a gentle steady 

 breeze ; a moist warm atmosphere, but clear near the ground, and not muggy ; a 

 cloudy sky, and no moon. Rain (if warm and not too heavy), though inconvenient 

 to the collector, is often accompanied by ' ' shoals" of moths, and even during 

 a thunderstorm many specimens have been obtained at sugar. Thirty examples 

 of Diphthera Orion were taken by an entomologist in the midst of a severe 

 thunderstorm, and though he tried for more on several nights apparently more 

 favourable, he did not see another specimen. Another moth, Dasycampa rubi- 

 ginea, has on several occasions been taken at sugar on cold nights, when not 

 another species was present. It follows, therefore, that sugaring on nights 

 which do not present the above mentioned favourable combination sometimes 

 "pays well." We must not expect always to have everything favourable, and 

 should perhaps consider it an occasion suited for sugaring that does not pre- 

 sent any symptoms decidedly bad. These we will treat of under — 



(5) When not to sugar. 



As a rule, then, the sugar will be of little or no use when there is — 



fa) An easterly " touch'' in the wind 



(b) Frost, or unseasonably cold weather. 



(cj Strong moonlight. 



(dj No wind. 

 While the following are not quite so adverse, but still bad — 



■(e) An unclouded sky, (often, but not unvariably bad. ) 



(/) A sultry muggy atmosphere. 



(g) After a thunderstorm, (according to Dr. Knaggs.) 



(h) Too many attractive flowers. Sometimes, however, I have seen flowers 

 swarming with one set of moths, and the sugar with another. When we find 

 that the flowers are attracting all the moths, we should sugar the flowers ; by 

 this their attractions are increased, and we are able to reap a large harvest off 

 them. Occasionally we find our sugar taken possession of by mice, toads, 

 beetles, ants, &c, which deter the moths from coming. In such a case we must 

 change our sugaring ground, or try some method of getting rid of the invaders. 

 Mice are seldom so numerous as to do much damage ; beetles and toads 

 I generally transfer to some other locality ; to the ants, if very numerous, it is 

 perhaps better to yield the ground. 



We must now return to the first division — " How to sugar ;" and see how we 

 are to reap the harvest of moths. First, then, we must provide ourselves with a 

 lantern. This should be something like a policeman's, but with a piece of plate 

 glass instead of a "bull's eye." It should be also furnished with a cord, by 

 which it may hang from the neck, or with a hook to fasten it to a belt round the 



