24(5 



HARDWICKE'S SCIENCE-GOSSIP. 



[Nov. 1, 1SGS. 



annoyance, was by curving its body completely 

 round, and by main force shoving the Nepa's fore- 

 legs off, with the end of its abdomen. This occurred 

 several times ; but gradually the Nepa became ex- 

 hausted, and at last was entirely eaten. Imme- 

 diately after this meal the pupa devoured a blue- 

 bottle fly. 



This brings us to the beginning of May, and 

 about the 10th of that month the pupa began to 

 refuse all kinds of food ; and knowing that its final 

 change was near, I took the precautiou of wrapping 

 some muslin round the end of the lath which was 

 out of water, for the pupa to fix its feet firmly into 

 whenever the change might occur. 



On the morning of the 26th, at 10 a.m., it crawled, 

 for the first time, out of the water, but shortly im- 

 mersed itself wholly in again: at mid-day it thrust its 

 head and thorax out, and so remained till 6.30 p.m.; 

 then, leaving the" water entirely, and climbing up to 

 the under side of the muslin at the top of the lath, 

 it remained stationary. It began now to lash its 

 abdomen, with rather violent jerks, from side to 

 side ; and whilst I was eagerly watching it, I ob- 

 served, exactly at 7.30 p.m., a bright green spot in 

 the middle of the upper part of the thorax. This 

 was the body of the Dragon-fly seen through an 

 opening in the skin. This opening (which, as far 

 as my experience goes, never extends beyond the 

 thorax) rapidly increased in size, and soon the head 

 and thorax of the Dragon-fly were clear of the old 

 integument : the legs were then smoothly drawn 

 out, and when the creature was sufficiently out of 

 the old skin to allow of its being done, the head fell 

 gently back, and at last hung completely down, 

 More and more of the abdomen was all this time 

 being gradually withdrawn, until at last I, and those 

 who were looking on with me, were greatly alarmed 

 lest the creature should fall down backwards, and 

 be seriously injured in its then soft condition, and 

 the climax of our observations be brought to an 

 untimely end. Instinct, however, had taught it 

 exactly when to stop, and at the end of five minutes 

 from the time the opening took place in the skin, 

 the Dragon-fly had performed the first act of the 

 operation of changing ; that is, it had pulled itself 

 out of the old integument as far as it then intended 

 to go, only leaving just enough of its abdomen still 

 in, to hang on by. 



In this strange position it remained, perfectly 

 motionless, for fifty minutes ; then quickly turning 

 up its head and clutching the old integument with 

 its legs, it entirely freed the remaining part of the 

 abdomen, leaving the old skin in a very perfect con- 

 dition, always excepting the hole in the thorax. 



Up to this moment there was no perceptible 

 change in the size of the wings : they looked almost 

 as if they were still in their small wing-cases : but 

 now began the most wonderful and critical part of 

 the whole operation. 



The Dragon-fly was clinging (head uppermost) to 

 the old skin, this old skin being firmly fixed to the 

 under side of the stick (the upper side would not 

 have answered the purpose) : and curving itself in 

 such a way that the wings, in their development, 

 should hang down without coming in contact, either 

 with its body or with anything else, the creature 

 appeared to devote the whole of its energies and 

 being to the most important object of producing 

 for itself a fully-developed uninjured set of wings. 



Gradually and beautifully did these delicate 

 membranes expand, and; grow downwards. This 

 operation took just twenty minutes, and when 

 ended the wings were about eighteen or twenty times 

 theii\original size ; but quite soft, and hanging close 

 to each other. 



I did not think it necessary to watch the creature 

 any more just then; but the next morning, on 

 opening the shutters of the room, a very handsome, 

 perfect Dragon-fly stood upon the table, with a bright, 

 green head and thorax ; abdomen striped black and 

 green ; black legs, and with its shining gauze-like 

 wiugs wide apart and quivering ready for flight. 

 It measured three inches in length (exclusive of its 

 abdominal appendages) and four and a quarter 

 inches across the wings. 



I took it out into a sunny part of the garden, and 

 in three minutes it soared up to the top of our 

 highest tree, and was lost to us for ever. 



This Dragon-fly had been kept in a warmish room 

 all the winter, and perhaps changed somewhat 

 earlier than it would have done in a natural state. 

 Two other pupse, which I procured after this one, 

 changed respectively on the 2Sth and 29th of May : 

 the opening in the skin of the former took place at 

 9.30 p.m., and of the latter at 10 p.m., and they 

 took about the same time as the first one described, 

 to accomplish the various parts of their final 

 change. 



It is somewhat remarkable that in all these cases 

 the changes took place either in the dark or at 

 dusk ; for there can be no doubt that, from the 

 time of the bursting of the skin till the Dragon-fly 

 is able to take flight, the creature is in a most help- 

 less condition, and would fall an easy victim to any- 

 thing attacking it. 



I ought to mention that the pupa (without the 

 horny appendages at the end of its abdomen) 

 measured just two inches. It did not increase in 

 size, nor did it change its skin, except finally, whilst 

 I had it. 



This then gives the entire history of the creature 

 for 54 months of its existence. 



It was curious that none of the pupa) I procured 

 ever died ; and on the other hand, out of several 

 larva;, I never could succeed in keeping one alive ; 

 but I had time to observe that the latter do not 

 appear to have the same use of their legs that the 

 pupa; have, for they never clung to a stick, but 



