208 ENTOMOLOGICAL NEWS. [June, '04 



softer leaves, especially of succulent annual weeds, are apt to 

 get too wet ; and if drops of water are observed on the inside 

 of the glass, remove the tin cover and close the top with a 

 piece of cheese-cloth held on by a rubber band . A day or two 

 of drying out is sufficient- 

 Each jar should be examined every day, both for the pur- 

 pose of seeing if any moths have emerged and to see that the 

 condition of the larvae is healthy, — in other words clean. 

 After a very little experience, it will be easy to observe when 

 the food is becoming stale or soggy or that too much damp- 

 ness is accumulating on the leaves or bottom of jar, all of 

 which will lead to mold and sickness. Then the larvae must 

 be changed to entirely fresh food and a clean jar. Select a 

 duplicate of the one they were in and place in it a moderate 

 quantity of the food-plant ; then dump out the contents of the 

 old jar on a large sheet of clean paper, and with fine forceps 

 carefully examine every fragment, picking up each larva deli- 

 cately with the forceps, — which will not hurt him if not 

 squeezed too tightly, — and drop him on the leaves in the fresh 

 jar. Should any pupae be found, it will be better to place 

 them in a separate jar or vial, where they need not be disturbed 

 again ; but be sure and write a duplicate label, so that the 

 identity will not be lost. 



The great majority of the larvae taken in the early part of 

 the summer, up to the middle of July, will emerge as moths 

 within one to three weeks after transforming to pupae. Some 

 of those taken later than this will live as larvae or pupae all 

 winter ; and species hibernating in this state must be kept 

 out-of-doors under as nearly natural conditions as possible. 



I have left to the end the subject of making notes and record- 

 ing observations of all larvae that are bred, as it is really the 

 most useful and important part of the whole work. The life- 

 histories and habits of our North American species of Micro- 

 Ivcpidoptera are so little known that up to this time less than 

 twenty per cent, have been described. So this field is one of 

 the easiest in nature in which a collector just starting can find 

 lots of room for original work. 



My method is as follows : — On the slip of paper in each jar 

 I write a number, and in a note-book (card index cards are bet- 



