314 Mr. Newport on the Natural History 
seems so completely to influence their movements, I have frequently inverted 
the phial that contained them, so that they were then at the bottom. In- 
stantly the whole were in motion, travelling in haste perpendicularly up the 
sides of the phial to that part which was then the top, and most exposed to 
light. I have then placed the phial in a horizontal position, with that end of 
it in which the larvee were collected furthest removed from the light, and 
again the whole were travelling rapidly towards it at the opposite end of the 
phial. In this way they can at any time be aroused to a state of great activity, 
especially if the light to which they are exposed is intense, whether it be 
artificial or bright sunlight. That it is light which acts thus powerfully 
upon them seems to be proved by the circumstance that, if the stopper be 
removed from the mouth of the phial when they are collected around it, and 
the phial be then placed in a horizontal position with its closed end to the 
light, the larvee do not attempt to escape through the opened mouth, although 
nearest to it, but instantly travel in the opposite direction towards the light. 
Thus the unerring influence of a great physical cause, that arouses the instinct 
of the newly-developed being, seems to be clearly indicated in the effects of 
light upon these Meloés. These effects I may perhaps be allowed to designate, 
—the polarization of Instinct. 
The influence which light produces on the instinct of the young Meloés 
accords with their presumed ascent on the bright-coloured flowers of the 
dandelion and buttercup, preparatory to their attaching themselves to the 
Hymenoptera that visit these flowers to collect pollen. Every circumstance . 
we are acquainted with respecting the Meloés seems to confirm us in this - 
view of their habits. Their extremely diminutive form, their lightness and 
activity of body, the celerity with which they attach themselves, and the per- 
tinacity with which they adhere to the objects within their reach, and their 
extreme susceptibility of external influences,—all coincide to prove their 
parasitic nature. They seem indeed in every respect most fitted and de- 
signed, by the Great Author of their being, to attach themselves securely to 
their victims, and be wafted about from flower to flower on the bodies of 
other insects; in the full joyousness of open daylight, while being conveyed to 
the proper locality for their development. This, doubtless, is the instinct 
that urges them to attach themselves to the Hymenoptera, to be carried to 
