PRESERVATION OF MUSEUM SPECIMENS. 551 



time is required for that purpose, as it takes at least two weeks to go through, all the 

 boxes carefully. 



It has been the fashion to recommend as a certain preventive tight boxes, and 

 quarantining all specimens before putting into the collection, and undoubtedly this 

 is an excellent precaution, saving much future labor. It is, however, by no means 

 the certain remedy it has been claimed to be. The boxes and cabinets in use in the 

 Museum are as perfect, as far as safety is concerned, as it is possible to get them at 

 present, yet withal constant care is required. Psocidce will find their way into the 

 tightest boxes, and though they do little damage ordinarily, yet in a collection of 

 Tineidce, or minute Diptera, they can do considerable damage. For these pests I have 

 found naphthaline a perfect remedy. A single half-ounce cone is a perfect protection, 

 and lasts about three months ordinarily. 



Tineid larvae are rather rarely found in the collections on the larger moths, and 

 are not always easily discovered, since they make no dust, as do the Anthreni. On 

 one occasion I found that one pair of wings of a C. regalis suddenly collapsed with- 

 out apparent cause. Close examination showed a Tineid larva that had been feeding 

 on the dense, long vestiture, making galleries in all directions in such a way that 

 when I took hold of one end of the gallery, the vestiture of the under side came off 

 in large sheets, leaving the wings almost clean, the veins broken here and there, 

 which produced the collapse. They rarely burrow into the specimen, never in my 

 experience. Ptinidce are sometimes found, but are exceedingly rare in our collection. 

 One box lined with corn pith was riddled by them, and a very few specimens were 

 attacked. By all odds the most dangerous enemies are the larvae of the Dermesiidce, 

 which are pests pure and simple. The principal enemy in our collection is Anthrenus 

 varius, though Trogoderma is not uncommon. 



My experience with these is, that in the uniformly high temperature preserved in 

 the laboratory they breed all the year around, and have no definite broods; a few 

 larva? appear at all times, though during the summer, when the beetles come in from the 

 grounds, and from other parts of the Museum, exposed specimens are attacked at more 

 regular intervals. The rule is to keep naphthaline in all boxes at all times, but, like 

 all rules, it is not always possible to adhere strictly to it. The boxes not so protected 

 are usually first attacked. In a cabinet not quite tight I coned a number of drawers 

 and left the others unprotected. In the course of the summer the unprotected drawers 

 nearly all became infested, while as a rule the others were free. The naphthaline 

 seems to act as a repellant. I have found, however, that it does not annoy the larvae 

 to auy very great extent, and Mr. Lugger has shown me a naphthaline cone in a hol- 

 low of which a larva had pupated. I have reason to believe, however, that it does re- 

 tard the development of young larvae. A large number of boxes, nearly one hundred, 

 were received from North Carolina, containing a collection, principally Coleop- 

 tera. They were overhauled and found to be pretty generally infested with Trogo- 

 derma, this being the only species found. No Anthrenus larvae were noticed. Bisul- 

 phide of carbon was freely used, and naphthaline cones were placed in all the boxes. 

 For awhile the boxes were frequently examined and no larvae developed. Through- 

 out the summer the boxes were examiued at intervals and remained free. With the 

 approach of cold weather they were left for a longer period and the cones nearly ail 

 evaporated. In December this was noticed, and the boxes were again overhauled, 

 and it was found that a very general development of larvae had begun, all of them 

 Trogoderma, and none of them more than 2 to 3 millimeters in length, most of them 

 apparently just hatched. The entire collection was scrutinized, and an occasional 

 Anthrenus larva was found, but no other Trogoderma, even in the most exposed boxes. 



I conclude from this that the collection when received was infested, and that there 

 were e^gs everywhere ready to develop ; some had begun to develop, and these were 

 destroyed by the use of bisulphide of carbon, which also served to check the develop- 

 ment of the eggs. The boxes were quite large, and two large cones were put in each ; 

 they were also quite secure, and the atmosphere in them was fully impregnated with 



