$ The West American Schntist. 



HINTS ABOUT KILLING LEPIDOPTERA. 



It is important when collecting insects, to preserve their form, 

 color, and scale-covering. With Lepidoptera the importance of 

 such care is evident. Manv rare and desirable specimens are 

 found to be, when captured, more or less diverted of their hypo- 

 dermal coloration ; such individuals should always be preserved 

 until replaced by better. 



Avoid hastily killing by pinching, as such a procedure 

 destroys the symmetry and relative position of the parts so 

 treated. Do not unthinkingly and carelessly grasp the wings ; 

 but, on the contrary, handle gently with forceps or fingers, being 

 careful to grasp the sides of the thorax from the under surface of 

 the insect without applying too great compression ; the append- 

 ages may often be utilized for this same purpose. The main ob- 

 ject being to preserve the natural appearance of the specimens for 

 study, and to give a neatness and perfectness to the collection, 

 which always reflects great credit upon the collector. 



The use of chloroform, ether and cyanide of potassium as 

 agents for destroying life is not entirely satisfactory, as a rigidity 

 is imparted to the muscular structures, rendering a quick and 

 easy manipulation difficult, owing to the persistency of the posi- 

 tions assumed at death. 



Exposure to the vapor of aqua ammoniae produces complete 

 flexibility, with the objection that it requires too long a time to 

 suffocate the larger species and the liability to bleach and destroy 

 the animal colors. An agent which will quickly kill and impart 

 relaxation to the muscles is a desideratum of great importance to 

 the collector of these fragile and delicately tinted insects. Such a 

 result can be obtained by the combined action of aqua ammoniae 

 and cyanide of potassium. 



Every collector of Lepidoptera should have two or three wide 

 mouthed bottles or jars of different sizes — the smaller to receive 

 the micro-lepidoptera; the larger ample enough to contain the 

 larger species of Sphingidse and Bombycidae. Each jar or bot- 

 tle should be prepared in the following manner : First place a 

 layer of cotton in the bottom thoroughly saturated with the am- 

 monia, over this is to be placed a thicker layer of dry cotton, 

 upon which the potassium should be placed and the whole sur- 

 mounted by another mass of cotton, covered by a piece of thick 

 paper, previously punctured and neatly fitted into the bottle in 

 such a way as to hold the cotton in place. 



The jars should at no time be long inverted. It is best to pre- 

 pare them a couple of weeks before using, then add a fresh sup- 

 ply of ammonia, and a good result can be expected. 



Such is my method for killing Lepidoptera, and I have had 

 excellent success, as shown by the rapidity with which I can 

 mount my specimens, with the removal of scales reduced to a 

 minimum. F. E. Blaisdell. 



Coronado, Jan. 6th, 1889. 



