93 



have been startled by the sudden appearance of a butterfly when none were apparently in 

 the neighborhood. 



The causes which lead to the attractiveness of decoys, no doubt, are various, possibly 

 the passing butterfly, on seeing the decoy, supposes the latter has found an abundance of 

 •suitable food. But my opinion is, that in the majority of cases it is a matter of sexual 

 importance, and but for this powerful influence which causes them to seek each other and 

 thereby propagate their species, these most beautiful objects of nature would eventually 

 die out. 



NOTES ON BOMBYCID^. 



BY FREDERICK CLARKSON. 



The habits of insects present an attractive and fruitful field of discovery, illustrating 

 in many remarkable ways their peculiar instincts, governed by heredity and more or less 

 conditioned by environment. The power, which we call instinct, controlling the habits 

 of insects has a regularity of action governed by ordinary conditions, but there are fre- 

 quent manifestations of adaptations to circumstances as conspicuous in the several orders 

 of insects as in the various races of mankind. The extraordinary condition can only be 

 regarded as an obstruction to the usual law that governs instinct and compels the creature 

 to conform to the changed surrroundings. The larvae oiBombyx Mori, if crowdedfor space,at 

 the time of pupation, will associate to the number of three or four in spinning the one 

 cocoon which covers them. The larvae of Samia Cynthia, under like surroundings, pre- 

 sent a similar variation of habit by spinning interior sections, one above the other, in. the 

 silk-lined leaf constituting the one envelope, so that outwardly it has the appearance of 

 a, long single cocoon. The marked feature of this dual cocoon is that while ordinarily 

 the place of escape for the imago is at the upper end of the cocoon, the inhabitant of the 

 lower section emerges at the lower end of the cocoon, from the lower end of its section. 

 The Oynthia worms occasionally from like necessity will to the number of two spin a 

 cocoon in common, and undergo transformation in the one interior section. I have col- 

 lected the past season very diminutive cocoons of P. Cecropia, and S. Cynthia, the 

 former measuring 1^ inches long by \ inch in diameter ; the interior section f inch long 

 by § inch in diameter ; the latter was spun on a leaf \\ inches long, the cocoon rather 

 less by | inch in diameter. The cocoons contained the larva dead and in a dried 

 condition. 



From a eocoon of P. Cecropia I have obtained a very small male, measuring scarcely 

 four inches in expanse of wing. The kidney-shaped spots on secondaries are reversed 

 from their usual position, the pointed end being directed towards the abdominal or inner 

 margin instead of, as commonly, to the exterior margin. The wavy white line bordered 

 with black, on the exterior margin of the primaries, which is usually more or less pointed 

 into the adjoining lilac, is in this specimen a line corresponding in form with that of the 

 margin of the wine:. 



DROVES OF LYC^ENID CATERPILLARS HERDED BY ANTS. 



BY MRS. WYLLY, OF INDIA.* 



The larvae of Tarucus theophrastus, Fabricus, are cultivated and protected by the 

 large common black ants of Indian gardens and houses. The caterpillar, which varies in 

 color from a light pure green to a dark reddish tint [this is a common variation in Lycaa- 

 nid larvae], is about three-quarters of an inch long, louse-like in shape, and slow in move- 

 ment, and it feeds on the Zizyphus jujuba, a small thorny bush of the jungles, with an 

 edible astringent yellowish fruit, the " Byr-coolie " of the natives. Some Lycaenidae 

 larvae have the power of protruding and retracting at will two small fleshy tentacles or 



* Reprinted from an article entitled " Butterflies and Ants," by Lionel de Niceville, F.E.S., in the 

 Journal of the Bombay Natural History Society, Vol III. p. 164 (1888). 



