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very far from being the case. For let any one examine stagnant waters at any time during 

 the months of August, September, or October, and from thence in any part of the follow- 

 ing winter, and he will find these very caterpillars at any of those times : and this, not in 

 any one particular year, but they will be found also in any one whatever, fully fed, and of 

 the largest size. Nor are the caterpillars of this species the only ones to be found fuUy 

 fed. Those of N". '2. belonging to the flat-bodied Libella, will also be found very 

 plentifully, many of them being of the first magnitude, together with numbers of the 

 same species, very voung according to the time of year when sought for ; and appearing to 

 have been hatched from those eggs that were laid by parent insects in the spring ; for such 

 I must conclude them to be, how else can we account for their smaUness, at the same time 

 that we may find others of the largest size ? We must not suppose there can be this differ- 

 ence of size in the same species, owing to some eggs having been laid three weeks or a month 

 sooner than others ; that, being so short a space of time as not to allow it possible for one 

 of those caterpillars to attain its full size, (and all the species of flat-bodied Libellas appear 

 within a month of each other.) Nor can we be so deceived as to mistake a species of the 

 long-bodied caterpillars, for one of the short-bodied ; the difference being extremely appa- 

 rent at the first glance. 



" These reasons appear to me so convincing, I should have thought myself inexcuseable 

 to have passed them over in silence, when I was giving the history of these animals. I 

 shall therefore think myself happy to have this circumstance corroborated by future expe- 

 rience, or rectified and cleared up, if found to be an error. I shall only say, I have dwelt 

 the longer on it, as it is an observation I never heard of before. I have likewise singled 

 out the largest Libella, and the flat-bodied ones for its illustration, as being more con- 

 spicuous by their size, and easier to be observed than those of the smaller sorts. 



" The two principles of hunger and lust, so apparent through the animal kingdom, are 

 in no class or tribe more manifest and visible than in these insects. The former I have 

 described and explained through their different states ; it remains for me to shew the man- 

 ner in which they obey the calls of the latter. And herein I must observe, that the different 

 manner in which the act of copulation is performed, depends on the difference of the respec- 

 tive kinds ; the organs of generation being placed in different parts of the body, according to 

 the distinct species. All the flat-bodied ones have those parts placed in common with most 

 other insects, at the extremity of the tail. In all the slender-bodied ones, the organ of 

 the male is placed next the breast, close to the part where the thorax and abdomen unite ; 

 while the same organ in the female lies in the very extremity of the tail, and the singular 

 manner of these creatures coupling is a circumstance worthy of observation. 



" As soon as they have arrived to their perfect state, the males seek out their mates, in 

 order to propagate their species ; for this purpose they frequent ponds and standing waters, 

 places where the females generally harbour, and when the male in the course of his flight 

 comes within a certain distance of her, if it be one of that species whose sexual parts 



I Q 



