270 THE XA TL 'RE- STUD i ' RE I 'IE W [ 2 : s-nov., .906 



The ends of the strips are dovetailed so as to lock together smoothly, 

 when bent into a rectangle, and thus the making of the frame is 

 reduced to a matter of a second or two. The material is white bass- 

 wood very smoothly finished and looks well as it is. Most people, 

 however, prefer to have the inside surface blackened so as to be less 

 conspicuous in the finished mount. This is done by laying a lot of 

 the strips on a sheet of newspaper and brushing over the inside sur- 

 faces with a flat brush and common writing ink. The frame is 

 glued to one of the glass plates, preferably with a flexible glue, the 

 insects arranged as desired and glued to the glass, the other glass 

 put on and the whole bound with a strip of black passe-partout. The 

 specimens should be fastened to the glass in the order of natural 

 sequence or development so as to read like the words in a line, viz., eggs, 

 larvae of different sizes, pupae, male and female, if distinguishable, and 

 male and female adult, and then add such bits of work of the species — 

 gnawed leaves, galls, borer channels, etc., — as there may be room for 

 in the case. They will thus tell to the' child the story of the life and 

 work of the insect, at a glance and in the characters of nature itself. 



The material used to fasten the insects to the glass has given some 

 trouble. I advised in my book that to prevent the glue from becom- 

 ing brittle and scaling off from the glass there should be added 20 

 drops of glycerine to the ounce of ordinary liquid glue. I have not 

 found this to work badly myself, but the complaints that have been 

 sent me from humid localities are convincing that this is not a safe 

 method. The glycerine is hygroscopic and may take up water enough 

 from moist air to cause the glue to liquify. Canada balsam 

 makes a good adhesive, but that is hardly available for 

 the ordinary school. Of late years I have added to very 

 thick liquid glue about one fifth its bulk of honey — after experiment- 

 ing with different proportions — and have found this to work well. 

 For the present this is the best material for the purpose I am able to 

 suggest. I am now experimenting with the "flexible glue" used by 

 book-binders, and find that it is likely to serve the purpose, but it 

 requires more time to make a thorough test. 



The problem of putting insect nature-study on a footing at once 

 reasonable and befitting its importance to the varied interests of the 

 country as a whole is a large one. The writer hopes that a number 

 of teachers may give to readers of The Review the benefit of their 

 experience with this line of work. 



