MEANS OF DEFENCE OF INSECTS. 445 



Various insects, doubtless, find the wonderful vitality^ with which they 

 are endowed another means of defence ; at least of obviating the effects 

 of an attack. So that, when to all appearance they are mortally wound- 

 ed, they recover, and fulfil the end of their creation. Indeed female Le- 

 pidoptcra, especially of the larger kinds, will scarcely die, do what you 

 will, till they have laid their eggs. Dr. Arnold, a most acute observer, 

 relates to Mr. MacLeay, that iiaving pinned Scolia quadrimaculata, a 

 hymenopterous insect, down in the same box with many others, amongst 

 which was the humming-bird hawk-moth (JSlacroglossa stellatarum), its 

 proper food ; it freed itself from the pin that transfixed it, and, neglecting 

 all the other insects in the box, attacked the Sphinx, and pulling it to 

 pieces devoured a large portion of its abdomen. 



We often wonder how the cheese-mite {Acarus Siro) is at hand to 

 attack a cheese wherever deposited ; but when we learn from Leeuwen- 

 hoek, that one lived eleven weeks gummed on its back to the point of a 

 needle without food, our wonder will be diminished.^ Another species of 

 mite (JJropoda vegetans) was observed by De Geer to live some time in 

 spirits of wine.^ This last circumstance reminds me of an event which 

 befel myself, that I cannot refrain from relating to you, since it was the 

 cause of my taking up the pursuit I am recommending to you. One 

 morning I observed on my study window a little lady-bird yellow with 

 black dots (^CoccineUa 22-puncta) — "You are very pretty," said I to 

 myself, " and I should like to have a collection of such creatures." 

 Immediately I seized my prey, and not knowing how to destroy it, I 

 immersed it in geneva. After leaving it in this situation a day and a 

 niffht, and seeins: it without motion, I concluded it was dead, and laid it 

 in the sun to dry. It no sooner, however, felt the warmth than it began 

 to move, and afterwards flew away. From this time I began to attend 

 to insects. — The chamaeleon-fly IStratyomis Chamceleon) was observed 

 by Swammerdam to retain its vital powers after an immersion equally 

 long in spirits of wine. Goedart affirms that this fly, on which account 

 it was called chamseleon, will live nine months without food ; a circum- 

 stance, if true, more wonderful than what I formerly related to you with 

 respect to one of the aphidivorous flies.'* — If insects will escape unhurt 

 from a bath of alcohol, it may be supposed that one of water will be less 

 to be dreaded by them. To this they are often exposed in rainy weather, 

 when ruts and hollows are filled with water : but when the water is dried 

 up, it is seldom that any dead carcasses of insects are to be seen in them. 

 Mr. Curtis submerged the fragile aphides for sixteen hours ; when taken 

 out of the water they immediately showed signs of life, and out of four, 

 three survived the experiment : — an immersion of twenty-four hours, how- 

 ever, proved fatal to them.^ 



The late ingenious, learned, and lamented Dr. Reeve of Norwich, once 

 related to me that he found in a hot fountain on the top of a mountain, 



' The penetrating genius of Lord Verulam discovered in a great degree the cause of this 

 vitality. " They stirre," says he, speaking of insects, "a good while after their heads are 

 off, or that they be cut in pieces; which is caused also for that their vital spirits are more 

 diffused thorowout all their parts, and lesse confined to organs than in perfect creatures.'" 

 Stflv. Si/lvar. cent. vii. ^ (i97. 



* Leeuw. Epist. 77., 1694. ^ £)e Geer, vii. 127. 



* Bib. Nat. ii. c. 3. * Linn. Trans, vi. 84. 



38 



