ENTOMOLOGICAL SOCIETY OF ONTARIO. 81 



occasion to confine a number of these bugs in a greenhouse upon cabbage plants over 

 which a breeding cage without a bottom was placed, earth being banked up about the 

 base of the cage. The bugs had been thus confined for a short time when during the 

 night, mice worked their way under the side of the cage, and in the morning all that 

 remained of the bugs consisted of a confused lot of heads, legs and fore wings, the mice 

 having clearly eaten the confined bugs during a single night. Still, as against persistent 

 and continual enemies these bugs may be and probably are distasteful, mice being only 

 occasional or accidental enemies. 



In commenting on the experiments of Professor Plateau, '• Science Gossip," perhaps 

 somewhat overestimating the value of the results obtained, says : — " It would indeed be 

 well if all the examples of 'warning coloration ' were subjected to as careful an ex- 

 amination. Equally cautious also should naturalists ba before accepting examples of 

 ' mimicry ' among animals and plants In some cases the so-called ' advantageous 

 mimicry ' falls to the ground, for the insect which is supposed to imitate one of its 

 fellows appears at quite & different time of year from it." 



Now, caution is a grand virtue, and should be, always, the investigators watchword, 

 but to be over cautious is to cheat ourselves and each other out of the truth, which prac- 

 tically amounts to little less than carelessness. He who cautiously winnows the grain, 

 Will be as careful that none is blown over with the chaff as he will be to keep the latter 

 from falling back into the cleaned grain, as, in either case, his work will be but poorly 

 done. 



By the way, has it ever been settled, beyond question, that both the species pro- 

 tected and the one protecting must occur, interspersed together, oyer the same area and 

 at the same time of year 1 Would either the ornithologist or entomologist be greatly upset 

 if he were to find that birds which had learned, by experience, in spring and while yet very 

 young, to shun insects of certain peculiarities of colour and movement, or which appear 

 to them to possess such characteristics, should continue to follow the same course in late 

 summer or autumn ? How soon do birds forget past experiences, and cease to profit by 

 them 1 After having learned that certain insects, having certain peculiarities of color or 

 of action are not fitted for food, will they not rather continue to profit by such experience, 

 and avoid such at whatever time of year and wherever they encountered them ? Besides, 

 does all of this education have to be acquired by experience, or does heredity not exert an 

 influence more or less important 1 



The adult of the Hickory tree-borer, Gyllene pictus, develops chiefly in Garya, and 

 emerges in spring, being almost exactly reproduced, so far as form and colour are con- 

 cerned, in the Locust tree-borer, Gyllene robinice, which develops in Eobinia pseudacacia, 

 and emerges in late summer. Both of these sp3cies are supposed to mimic wasps, but 

 we will suppose that both wasps and borer have disappeared before the latter species of 

 borer has emerged ; would it not gain some protection from its close resemblence to the 

 borer that had preceded it, several months earlier 1 ? Would entomologists be very much 

 astounded if such conditions should be found to obtain among other spscies ? 



Adults of our Podosesia syringce, resemble, very closely, both of our common species 

 of Polistes, P. annularis and P. metricus, especially on the wing, and when at rest the 

 abdomen of the moth is bent downward posteriorly and kept in constant motion, pre- 

 cisely as with the Polistes. If the moth is on the ground it does not read'ly take flight, 

 or, like many other moths remain quiet, but moves about in precisely the same manner as 

 the wasps. In this case a defenceless moth is not only, in all probability, protectively 

 colored, thereby resembling an entirely different insect, armed with a formidable weapon 

 of defence, but its movements are equally like those of the armed species, so that it must 

 gain protection thereby, to greater or less degree. But if one were to hunt for Polistes, 

 he would hardly select for his collecting ground a lilac bush long since out of bloom. He 

 would be far more likely to search for them on flowers, where he would seldom if ever 

 find Podosesia 



Do we not here have grounds for doubting the necessity for the mimicking and 

 mimicked forms occurring together over the same area, and if so, hosv far may they not 



6 EN. 



