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ture of coal plants than was ever expected by such a man as Mr. Nicol. There 

 was in the British Museum a large and interesting collection of fossil woods, as 

 well as a considerable number of Mr. Nicol's sections. Mr. Leifchild further 

 illustrated the subject by reference to some sketches of wood sections, and con- 

 cluded his remarks by a humourous account of what he termed the Pursuit of 

 Botanical Knowledge under Difficulties, whilst endeavouring to obtain some 

 further information upon the subject. 



A cordial vote of thanks to Mr. Leifchild, for his interesting communication, 

 was proposed by the President, and carried unanimously. 



The Secretary read a paper by Mr. W. H. Furlonge, " On the Anatomy of the 

 Flea;" also a note from the author, explaining that in consequence of being 

 obliged to go to Ireland he was unable to make some alterations and corrections 

 in the MS., and asking permission to do so before the paper appeared in print. 



The President moved a vote of thanks to Mr. Furlonge for his paper, and also 

 that an opportunity be aiforded him of modifying some of the opinions therein 

 expressed, as requested in his letter. 



Both propositions were at once cordially assented to, and carried unani- 

 mously. 



Mr. B. T. Lowne spoke at some length on the anatomy of the flea, and dif- 

 fered considerably from Mr. Furlonge's conclusions, although he thought most 

 of the descriptions were fairly accurate. Mr. Lowne chiefly objected to the 

 idea that the organ behind the eye is an organ of hearing ; he thought Mr. 

 Furlonge's evidence on that point was entirely imaginary. He also stated that 

 Mr. Furlonge was quite wrong about the sacs in the tarsi. Mr. Lowne said if a 

 flea be killed by chloroform and immediately immersed in glycerine and viewed 

 by reflected light the whole tracheal system appears as if injected with mercury. 

 The sacs in the tarsi so viewed are evidently merely ordinary tracheal sacs such 

 as abound in the stag-beetle and in many other insects. The speaker was of 

 opinion that Mr. Furlonge had mistaken the tendon of the last tarsal joint for 

 the main tracheal tube of the limb, and hence his assertion that he could not 

 trace the communication between it and the sac. Mr. Lowne further stated 

 that he had isolated the tracheal tube, and found the sac in question to be a 

 mere tracheal enlargement without any trace of contractile walls, but marked 

 by the ordinary spiral fibre. With regard to the contractions of the sac, the 

 speaker stated that they were due to a disturbance of the other respiratory or- 

 gans. In support of this view he stated that if a flea be examined alive without 

 subjecting it to pressure the sacs in question do not exhibit any contractions 

 until chloroform is administered to the insect, but that during recovery the 

 contractions described by Mr. Furlonge always occur. He examined a living flea 

 by surrounding it with cotton wool loosely, so that it remained entangled in the 

 fibres when in the live box. Mr. Lowne ascribed the pulsation in the sacs to the 

 withdrawal of air from them during the inspiratory dilation of the thorax and 

 abdomen, the valves of the spiracles remaining closed, instead of opening in the 

 normal manner. He thought that any injury or pressure would be liable to act 

 on the nervous system, and produce a similar result. Mr. Lowne horied mem- 

 bers would try the simple experiment indicated, and they would then be con- 

 vinced that the contraction of the sacs was an effect and not a cause of the cir- 

 culation of air, and likewise that it did not occur under normal conditions. Mr. 

 Lowne then drew attention to the relation of the tendon moving the last tarsal 

 joint with the sac, and stated that the contraction of the muscle moving the 

 tarsus by drawing on the tendon caused it to compress the sac slightly, and so 



