134 DIRECTIONS FOR COLLECTING, ETC. 
containing a chrysalis, from which eventually issues a small fly, which, in its turn, seeks some unhappy caterpillar, 
and, by means of its sharp ovipositor, places a number of eggs in its body, which, quickly hatched by the warmth, 
feed upon its vitals till it is destroyed. The ichneumon of the small silken cocoons, mentioned above, seems to 
confine its ravages to the caterpillars of the cabbage-white butterfly ; but each specics has its peculiar foe of this 
description, some large and some small, the former depositing only one or two eggs in the body of each caterpillar, 
the latter from ten or twelve to near a hundred: I have seen a caterpillar of the lacquey moth wince under the 
repeated punctures of its ichneumon foe, till it has at last fallen from the branch upon which it was feeding ; it, 
however, soon resumes its food, doubtless with redoubled rapacity, to satisfy the insatiate legion within, till, over- 
come by exhaustion, it crawls away to fix itself in some solitary place, where the chrysalis is found. 
After the season of collecting is entirely over, or when bad weather confines the student to the house, he may 
occupy his leisure time in arranging his collection; and I would strenuously advise him to do so, not merely as a 
pretty display of beautiful objects, but with due regard to nomenclature and system. Doubtless the most deeply 
interesting portion of natural history is the observation of the habits, physiology, structure, and properties of 
organised creatures (by far the greater number of which belong to the entomological division), but their proper 
and convenient arrangement, aceording to the most recent terms and system of science, is absolutely necessary 
for the successful progress and application of all knowledge ; and even those who are confining themselves to the 
arrangement of the mere nomenclature of the catalogue, are doing good service to the advancement of the science. 
The elaborate and searching observations of Reaumur and Bonnet would have been much more valuable had they 
been conducted with such a view to system and arrangement ; whilst as it is, (as mentioned in Kirby and Spence’s 
Introduction) some of the insects of which they have recorded the most interesting circumstances, cannot, from 
their neglect of system, be at this day ascertained. No one, for instance, knew Reaumur’s Abeille tapissiére until 
Latreille, happily combining system with attention to the economy of insects, proved it to be a new species, 
Megachile Papaveris. Even with the assistance of carefully-coloured portraits, it is almost impossible so to 
describe insects as to render them recognisable with certainty, unless the accepted terms and system of science 
be also employed; and Mr. Westwood, in his Entomologist’s Text-Book, alludes to the fact that many rare 
insects, of which engraved portraits have been given by the early entomologists, have from this cause been 
thought to be new species. 
Kirby and Spence affirm that a well-arranged system, with proper terms and names, is as necessary to the 
understanding of a science as is a dictionary to the understanding of a foreign language. “The labours of a 
Michaelis or a Laplace might be sealed books to us without dictionaries of the French and German languages ; and 
in fact a good system of insects, containing all the known species, arranged in appropriate genera, families, 
orders, and classes, is in reality a dictionary, enabling us (without the incalculable loss of time which would other- 
wise occur) to ascertain the name of any given insect, and thus to learn all that has been recorded of its properties 
and history, as readily as we determine the meaning of a word in a lexicon.” 
As far as regards the systematic position of any insect connected with the order treated of in the present 
volume, the student will have, comparatively, little trouble. The veriest tyro will at once know that any 
butterjly or moth must belong to the order Lepidoptera. Ue will perceive that as a butterfly it must belong to the 
section Diwrna ; a few striking characteristics will show him to which family he must refer it, and it then only 
remains to ascertain its genus ; and supposing it to belong to the genus Vanessa, it will not be at all diilicult to 
