FOES. 25 



chased very cheaply. We will, however, say this much 

 about cabinets : to be of any use they must be thoroughly 

 well made, and that by some one who understands their 

 use. Cheapness is therefore out of the question so 

 much so, that a good secondhand cabinet will generally 

 fetch as much as when it was new. 



The store-cases referred to above are made of thin, 

 light deal, and resemble large collecting-boxes. They are 

 corked and papered top and bottom, and are made to 

 close very tightly, so as to exclude as nearly as possible 

 the external air, and with it the enemies to the insects 

 within. Store-cases are made in several sizes, the most 

 convenient, in my opinion, being the two whose measure- 

 ments are loin, by Sin. and nin. by i6in. Tjjro of the 

 former are equal in length to one of the latter, and of 

 nearly the same width. They are both 2fin. in depth. 



Foes. 



Preserved butterflies have many enemies, which must 

 be carefully guarded against. Cockroaches, clothes-moths, 

 small beetles, and such animals will get at them if the 

 slightest chance is given ; but these are large enough to 

 be easily fought against. The worst enemies, mites (dust- 

 lice, Fig. 8) and mould, are much more insidious. Mites 

 are so small that, let the cases be closed as tightly as 

 they may, there will probably still be space enough for 

 them to enter, and enter they will unless deterred in 

 some way. Camphor was generally prescribed for this 

 purpose. Camphor, however, will not destroy mites : at 

 the most it will only tend to prevent their appearing ; 

 but let them once get into a case, camphor will not drive 

 them away. A more powerful agent naphthalene is now 

 used a great deal. As long as this is present the butter- 

 flies are almost or quite safe. Just as camphor is, it 



