LYC^XA II., III. 11 



ined carefully j'our larvtc, and some in alcohol of Lyca^na Argus and Corydon. 

 All have the origans alike. On the iienultunate seo;ment vou find outside and 

 behinil the stigmata two large white spots, each one of which evaginates a white 

 membranous tube, just like the finger of a glove, the top of which is not entirely 

 drawn out. I have seen the tube frequently, and if I blow a little the tube is in- 

 vaginated instantlv. On the antepenultimate seu;ment is a larger and tranversal 

 opening behind and between the stigmata near the apical border. It looks like a 

 closed month witli its lips, but I have not seen anything protruding from it. 

 But in an alcoholic larva of Arqun T saw an ovoid eva"iuation." Dr. Hajxen also 

 refeiTcd me to a paper by M. Guenee, Ann. Soc. Ent. de France, ser. 4, Vol. VII., 

 18G7, pp. 696-7, and Plate 13, in which are described and figui-ed similar organs 

 in Lyctena Bcefica. This author relates that whde observing tlie larva of Bcedca 

 he noticed two openings altogether like those of the stigmata, and as he turned 

 the caterpillar about it suddenly made spring out of tliese holes a peculiar body, 

 which he cannot compare to anything better than to the tentacles which certain 

 polypi put forth at will. And describing these, he goes on to say : " At the 

 summit of the 10th segment" (the lltli, counting the head as one), "is found 

 another opening placed transversely and surrounded by a raised pad. From the 

 middle of this opening comes forth, at the will of the caterpillar, a sort of trans- 

 parent, hemispherical vesicle, which gives escape to a fluid sufficiently abundant 

 to form a good-sized drop, which reproduces itself wdien it is absorbed. The cat- 

 erpillar only secretes this fluid wdien it is disturbed. ... As to the end which 

 nature proposes by this exceptional structure, it is not easy to divine it." 



In 1878, 1 was able to make more satisfactory observations, beginning with the 

 larvfe of Pseudargiolus, on Rattle-weed, and experimented in various ways on 

 both larvfe and ants. In each subsequent year I have continued the observa- 

 tions, and in 188.3 especially I lost no opportunity. The ants, when discovered 

 on a stem, are almost invariably on or near the larvoj. They run over the body, 

 caressing incessantly with the antenna?, and undoubtedly with the object of persuad- 

 ins: the larva to emit the fluid from 11. Much of the caressing is done about the 

 anterior segments, and while the ants are so employed, or rather while they are 

 absent from the last segments, the tubes of 12 are almost constantly exposed to 

 full extent, and so remain, without retracting, until the ants come tumbling along 

 in great excitement, and put either foot or antenna directly upon or close by the 

 tubes, when these are instantly withdrawn. The ants pay no heed to the tubes, 

 so far as touching them with intention, but at once turn to 11, caress the back of 

 that segment, put their mouths to the orifice there, and show every sign of eager 

 expectancy. By holding a hand-glass on 11, a movement will speedily be appar- 

 ent, and there will protrude a dark green mammilloid membrane, from the top 



