Moths of the Limberlost | Page 6

their relatives. Modest and lovely Modesta belongs with the Smerinthinae group; and there are others, feeders and non-feeders, forming a list too long to irncorporate, for I have not mentioned the Catocalae family, the fore-wings of which resemble those of several members of the Sphinginae, in colour, and when they take flight, the back ones flash out colours that run the gamut from palest to deepest reds, yellows, and browns, crossed by wide circling bands of black; with these, occasionally the black so predominates that it appears as if the wing were black and the bands of other colour. All of them are so exquisitely beautiful that neither the most exacting descriptions, nor photographs from life, nor water colours faithfully copied from living subjects can do them justice. They must be seen alive, newly emerged, down intact, colours at their most brilliant shadings, to be appreciated fully. With the exception of feeding or refraining from eating, the life processes of all these are very similar.
Moths are divided into three parts, the head, thorax, and abdomen, with the different organs of each. The head carries the source of sight, scent, and the mouth parts, if the moth feeds, while the location of the ears is not yet settled definitely. Some scientists place hearing in the antennae, others in a little organ on each side the base of the abdomen. Packard writes: "The eyes are large and globose and vary in the distance apart in different families": but fails to tell what I want to know most: the range and sharpness of their vision. Another writer states that the eyes are so incomplete in development that a moth only can distinguish light from darkness and cannot discern your approach at over five feet.
This accords with my experience with Cecropia, Polyphemus, Regalis, and Imperialis. Luna either can see better, hear acutely, or is naturally of more active habit. It is difficult to capture by hand in daytime; and Promethea acts as if its vision were even clearer. This may be the case, as it flies earlier in the day than any of the others named, being almost impossible to take by hand unless it is bound to a given spot by sex attraction. Unquestionably the day fliers that feed--the Sphinginae and Choerocampinae groups--have fairly good vision, as also the little "Clear-wings" tribe, for they fly straight to the nectar-giving flowers and fruits they like best to feed upon, and it is extra good luck if you capture one by hand or even with a net. It must be remembered that all of them see and go to a bright light at night from long distances.
Holland writes: "The eyes of moths are often greatly developed," but makes no definite statements as to their range of vision, until he reaches the Catocalae family, of which he records: "The hind wings are, however, most brilliantly coloured. In some species they are banded with pink, in others with crimson; still others have markings of yellow, orange, or snowy white on a background of jet black. These colours are distinctive of the species to a greater or less extent. They are only displayed at night. The conclusion is irresistibly forced upon us that the eyes of these creatures are capable of discriminating these colours in the darkness. We cannot do it. No human eye in the blackness of the night can distinguish red from orange or crimson from yellow. The human eye is the greatest of all anatomical marvels, and the most wonderful piece of animal mechanism in the world, but not all of power is lodged within it. There are other allied mechanisms which have the power of responding to certain forms of radiant energy to a degiee which it does not possess."
This conclusion is not "irresistibly forced" upon me. I do believe, know in fact, that all day-flying, feeding moths have keener sight and longer range of vision than non-feeders; but I do not believe the differing branches of the Catocalae group, or moths of any family, locate each other "in the blackness of night," by seeing markings distinctly. I can think of no proof that moths, butterflies or any insects recognize or appreciate colour. Male moths mate with females of their kind distinctly different from them in colour, and male butterflies pair with albinos of their species, when these differ widely from the usual colouring.
A few moths are also provided with small simple eyes called ocelli; these are placed on top of the head and are so covered with down they cannot be distinguished save by experts. Mueller believes that these are for the perception of objects close to a moth while the compound eyes see farther, but he does not prove it.
If the moth does not feed, the mouth parts are scarcely developed. If