MATING LIVE BUTTERFLIES. 



By Prof. John H. Gerould 



of the Department of Biology, Dartmouth College. 



No elaborate outdoor quarters are needed for keeping and mating live 

 butterflies. The air of the laboratory needs only to be fresh and fairly moist, 

 as that of the ground-floor rooms of large buildings of brick or stone is likely 

 to be in summer. The parched air of a steam heated room, or of one upon 

 an upper floor and flooded with direct sunlight, is more fatal to butterflies than 

 complete absence of food in a moist atmosphere. Bottomless cages 1 5 inches 

 in length and breadth and 1 inches high,, consisting of a simple frame of pine 

 strips covered inwardly with cotton mosquito netting, are of ample size for 

 Colias philodice, serving as a vivarium for the pupae, as an enclosure for 

 mating, and as a cage for the female during egg-laying, if the foodplant is 

 small enough to be covered by a frame of this size. The use of wire screening 

 is not to be recommended for adult butterflies, as it soon wears out and dis- 

 figures the wings that beat upon it. A frame of this sort covered with cheese 

 cloth, or better with the material known by milliners as frame covering, makes 

 an excellent breeding cage for even the youngest larvae. 



The larger the cage, the smaller are the chances that two individuals will 

 meet. I began my experiments by turning butterflies loose in a large screened 

 veranda, strongly lighted only on one side. Under such conditions their 

 attraction towards the light absolutely controlled them. Each went his or her 

 own way, paying not the slightest attention to the others. If several males and 

 females of the same species are placed in a cage of the dimensions noted above 

 ( 1 inches high and 1 5 inches square) or 1 5 inches in all three dimensions, and 

 kept in the direct sunlight, or, if the temperature is high enough, in strong 

 diffuse light, some matings may be expected. As soon as a couple are mated 

 they should be removed to a sepaiate cage, and their numbers noted. Mating 

 continues in Colias philodice for over an hour, usually for about an hour and a 

 half, and often two or three hours, so that there is little danger of promiscuity 

 when large numbers of both sexes are placed in the same cage, if properly 

 watched. One male often can be mated on successive days with several females. 



Papilios need large cages, 6 feet square or such a matter for mating, and 

 the cages need to be shaded. Otherwise the occupants will not come to the 

 foodplant but will beat against the top of the cage and pay no attention to 

 their food, i. e. moistened boquet. Of course a wild Papilio polyxenes wiil 

 deposit her eggs on carrot or parsley while enclosed in a small cage, 1 8 inches 

 square for example. For mating, the larger cages seem necessary. For Papilio 

 turnus I build a cage 6x6x12 feet over young hop trees (Ptelea.) 



A GIRL TEACHING BEGINNERS. 



Edward F. Bigelow, President of the Agassiz Association, writes: 

 "You are surely situated to do a great amount of good work in instruct- 

 ing young people and I believe that you will have great influence with them. 

 The reason we are thoroughly desirous of helping you is because I think your 

 lessons will be more instructive than coming from older naturalists. In the 

 nearby town of Stamford, a banker requested me to refer him to some young 

 person who could walk with his children and some of the neighbor's children. 

 I offered him my own services and he said, 'Oh, no, that would not do. The 



