THE SUBCOSTAL NERVURE IN THE WINGS OF INSECTS. 379 



such as appertains to all sensory nerves. To what I have already advanced on this point 

 I have nothing' to add. 



At the time of writing his article ahove mentioned, Leydig had not seen my second 

 paper on the antennal organs. Nor had he been successful, as he owns, in applying the 

 bleaching process I have recommended for their examination ; consequently neither has 

 he, nor indeed any writer (Lespes for instance, nor his critic in this subject, Claparede), as 

 yet noticed j^roperly the structures I have pointed out in the antennse. Under these 

 circumstances we must consider their opinion as to the seat of the auditory function 

 liable to revocation. 



EXPLANATION OF THE FIGURES. 



Fig. I. Termination of nerve of haltere in Rhingia rostrata, showing a row of ganglionic cells, with 

 nuclei a a, and their terminations b, b. 



Fig. 2. Two ganglionic cells in situ in halteres of £j-w/a/is tenax: a a, ganglior ic enlargement; 6, terminal 

 expansion with nucleus, c, passing to the interior of the vesicles, d. 



Fig. 3. Row of ganglionic cells, a a, in Eristalis tenax ; b, their termination beneath the vesicles. 



Fig. 4. Ganglionic cells in a Beetle (one of the Lamarice), the outer nerve-sheath attached to the skin- 

 canal ; a a, nuclei, two or three in each : a small tube passes through the skin-canal to the 

 closing-in membrane. 



Fig. 5. Shows one of the ganglionic cells with three nuclei, a a; the nerve-sheath, b b, has been attached 

 to the inner surface of the skin-canal. 



Fig. 6. Shows another form, where the ganglion, a, is not so near the integument as in the preceding. 



Fig. 7. Organs viewed in situ from above on the nervure of Strangalia elongata : a a, ganglionic swellings 

 with nuclei ; b, closing-in membrane and skin-canal. 



VOL. XXIII. 



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