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XXII. On the Neroe proceeding to the Vesicles at the Base of the Halteres, and on 

 the Sitb-costal Nervure in the TFings of Insects. By J. Braxton Hicks, M.D. 

 Bond., F.B.S. 



Read June 20th, 1861. 



It is unnecessary to enter into any description of tlie vesicles of the halteres and wings, 

 as I have already fully noticed them in former j)ages of the Transactions and Journal. I 

 showed first, also, of any observer, that to them a very large nerve proceeds, next in size 

 to the optic, and that the divisions of this nerve pass to the base of the vesicles. 



The additional information, which it is my desire now to lay before the Society, is, that 

 a bipolar ganglionic cell is to be found just beneath these organs. 



If, instead of viewing the parts intact, the base of the haltere be broken up, it will be 

 found that, shortly before arriving at the position of these vesicles, the nerve enlarges in 

 the following manner : — Each fibril is developed into an elongated ganglionic cell, gene- 

 rally with a large nucleus {a, figs. 1, 2, 3). The distal end becomes contracted again 



lu 



for a short space, but finally and gradually dilates, until it comes in contact with the inner 

 surface of the vesicle {b, figs. 1, 2, 3). In this terminal expansion I have sometimes 

 observed a nucleus (c, fig. 2) ; sometimes, however, the contents have been granular ; 

 whether there be a smaU cell at the very extremity, I am unable to say with any certainty, 

 but comparing it with its homologue in the subcostal nervure, I am inclined to think 

 the existence of such a structure doubtful. 



