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more thah a year from coming forth in winter and thus perishing for want of food. This could not fail to happen were their lise and their changes sixed tea number of sta- . ted days : whereas a degree more or less of cold being capable not only to retard their operations but even to suspend the whole effect of them for a very long time, they are thus prevented from coming forth at a time when they could not sind food.
Page 69, 1. i1.
Same a ivhole year. And even much longer. A caterpillar of a large size which seeds on the alder, and prpjikices k Tenthredo, did not appear in its persect state till two and twenty months after it had inclosed itself in its cone, altho' in order not to retard its transformation I kept it in a pretty warm place. .
Page 69,1. 17.
Some have this remarkable property. Tt must not be supposed from this that the fame winged insect issues twice ayear from the chrysalis; this never happens: it is to be underHood of those insects which breed twice a year. ".
Page 69,1. 23.
Plants an j leaves. That is, such as have'occasion for such substances. Many winged insects do not eat at all. Some species of this kind issue from their chrysalis at the end of Autumn, and even in the middle of winter.
Page 71, 1. 23.
With biobs. These knobs are more remarkable than they appear to be. Perhaps I shall hardly be believed when I assirm that they are the male organs of generation. I am however certain of the fact, as I have more than once seen certain species of spiders use them in this way. The males of this genus have their body more slender and their limbs longer than the semales. It is a laughable enough scene to see them making love. Both mounted on their web, approach each other with circumspection and measured step. They extend their legs, shake the web a little, and pat each other with their foot as if they durst not approach. After this contact, sear often seizes them, they let themselves fall with precipitation, and remain for some time suspended by
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their thread. Afterwards they take courage again, ascend anel" pursue their former courle. Afrer having patted each other sor along time with equal distrust- on both sides, they begin to draw nearer, and to become more familiar. Now the mutual patting becomes more frequent and bolder; all fear ceases, and at last from this introductory dalRance, the male sinds himself in a condition to terminate die business. One of the knobs of his antennsfi opens suddenly as if by a spring, and there appears a white bodyj the antenna folds itself under the belly of the semale, and the white body attaches itself to that part a little lower than the breast, and performs the s unction for which nature hath destined it.
If we did rsot know that spiders hate one another so naturally that they never meet, except at the season of engendring, without killing one another, we could not but be surprized at the-strange manner in which they, make love : but when we are acquainted with the reason os their cautious behaviour nothing appears-strange ; and. we cannot but admire their circumspection and care, not to deliver themselves-up blindly to a passion, which if imprudently yielded to, might prove fatal to them. This is a lesson which they give the Reader:
PAGE fr. I. penult.
Those of the male are smaller, shorter, &c. As the antenna: ot the m.de are generally larger than those of the semale, itwould ndt have been amiss had the author given us' some instance of'the contrary.
Page. 7*. I. 3.
*' In feme species- the male only has wings. This is the <&sc with aphides. The auth< r, on the authority of Friseh.
This is a circumstance which ought' to be examined j< for th6se who have studied the aphides have found that those with wings, as well as the others brought forth young. In the mean time other examples may be given of the author"s" assertion. The males of the glow-worm, those of two sorts of caterpillars with horns, those of several species of Geometry have wings, but the females want them. Lyonet.
Page 72,1. 4.
* The semale of the great black com beetle, has only two small membranes instead of wings. The Author.
The female butterflies of some species of Geoaietrse have likewise very small ends of wings.
Page 72, 1. 12.
A tube liftger cr shorter*. Hcnow some species of ichneumons whose tube is neatly two inches Jong, The large tail which some species of gralshoppers have, especially these of •the larger size, and which the common people suppose to be the male organ, is really that of the L-niale whp__ makes ,« 4ise of it sor laying -her eggs in the earth.
Page 75, I. first.
Which would perish in fresh water. This is a singularity as remarkable as that mentioned by Swamm. rdam in his Biblia Natune; that the larva of the Alilus lives equally well in salt water as in freflb.: it is not however without example among other animals. We know that the hlmoa and the Iliad come to freth waters to deposit their spawn: and perches are found in sea-water; but what perhaps will appear unexarrpled, is the worm which M. Reaumur-found ■could live sour and twenty hours in spirit of wine.
To this observation of Reaumur's, though not immediately connected with the subject of the Note, we lhall here take occasion to add a -very singular instance of tenacity of life in a species of insect, the Tenebrlo mortisagus Lin. made -by Mr Henry Baker, and recorded in the Philosophical Transactions, Numb. 457. P. 441
M I chose one of the largest of these beetles, (fays Mr B<iker,) and threw it into a cup fu'l of common lamp spirits, and in a few minutes it appeared to be quite dead. Whereupon I Ihut it up in a round pill-box ot about an inch and half di.imeter, and carried it in my pockt-t next day to London, where I.tossed it into a drawer, and thought no more of it for above two months after; when opening the box J found it, to my great surprize, aiive and vigorous^ Having however no intention of keeping it alive. I again plu.'.ge'l it into spirit of wine, and let it lie considerably longer than the first time, till supposing it deaii beyond any poffi'M.ity of recovery I put it intothe box again, and locked it in my drawers without looking any more at it for a monrh at 'east, when I found it again alive. And now! began to imagine mere must be somewhat extraordinary in this creature since it could survive the force of spirit of wine, which soon kilis most
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other insects, and live for three months without getting any sustenance.
A sew days before this, a friend had sent me three or four cock-roaches (Blatta orientalis) brought alive from the West Indies. These I had placed under a large glass of six or seven inches diameter, made on purpose to observe the transformation of caterpillars; and now 1 put my beetle amongst them, that he might enjoy a greater slufe of liberty than he had done for thiee n-.onths before. I sed them with green ginger, moistened in water, and they eat is greedily, but I could not sind, nor do I believe that the beetle ever tasted it during the whole sive weeks they lived under the glass together. Perceiving the Coch-roaches begin to decline in vigour, I was afraid they would lose much of their beauty, if I permitted them to die of sicknes:; wherefore I put them into spirit of wine, and the beetle their companion with them. They appeared dead in a sew minutes, and I believe were really sb ; "the beetle seemed likewise in the same condition; whereupon, after they had lain in spirits about an hour, 1 took them out, and whelmed the glass over them, till I lhould have leisure to dispose of them as I intended. This was about ten o'clock in the morning, and I saw them no more till evening, but found the beetle then creeping about as strong and vigorous as ever; and therefore I resolved to put him to a trial I imagined he could not poflibly survive, which was to let him remain a whole night in spirits; but here too 1 found myself mistaken ; for after he had been taken out a day, he appeared as lively as if nothing had happened to him.
Since that time I have put him no more in spirits, but have kept him under the glass afore-mentioned, where he is alive at present: though during the two years and half he has been in my possession, I have never been able todiseover, that he has drank or eaten any thing. In the exhausted receiver, where I have kept him sometimes for half an huur, he seems persectly unconcerned, walking about in vucuo, as briskly as in the open air ; but upon admission of the air, he shrinks his legs together, and appears in a surprise for near a minute."/ '-'
It is added in a Postscript, that this beetle (after being kept half a-year longer) was permitted to get away by tin; • carelessness carelessness of a servant, who took down the glasi to wipe
Page 75,1. 3.
Cannot live but in fresh waters. There are found in the Saltze, a small rivulet near Nordhausen, brown inledts with six legs, which live in cases hardly half an inch in length. These cases end in a point, and are not so gross as a straw: they seem to be constructed of all sorts of rubbish glued together, something like the nests of swallows. The Author.
There are many insects of this kind, and each species has its own particular way of fabricating their cases. Some construct them with an art and regularity that cannot be enough admired. Of this kind are all the different species of Phryganeas. Lyonet.
Page 75, 1. 30.
Food to the animals of both elements. The insects which may be considered as amphibious, are not all so in the fame way. There are iome which after having been aquatic under one form, so change their nature upon quitting the water, that if they should afterwards fall into it, they would be drowned. Others grow, live and undergo their, transformations in the water; after which they live in both elements. Some, as er having been produced in the air, plunge into the water, and remain there till they acquire wings, when they become again inhabitants of the air. Many species are produced, and grow in the water, change into nymphs in the earth, and pass their persect slate in the water, and in the air, but chiefly in the former. Lastly there are some which pass their larva state under the water, without being aquatic except in the head; the rest of the body is never wet; it is always surrounded with a volume of air considerable enough to permit a free respiration. These insects after their last change live only in the air. What a diversity!
Page 75, 1. 35.
ProteBion againjl the rigours of winter. All insects which retire into the earth are not induced to do so merely to avoid the cold. The greater part enter the eaith in order to undergo their transformations there, and others to lay their eggs.