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SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. y"] 



campaniform organs on the halteres of Diptera, according to Pflug- 

 staedt (1912), there is a similar sense rod (fig. 15 D, SR) attached 

 by a chitinous plate to the under surface of the dome {Po). The 

 rod in these organs contains an elongate apical body (AB), which 

 is evidently the same structure as that termed the " manubrium " by 



AB AB 



AB 



AxF 



AxF 



Fig. 15. — Various forms of sense rods, or scolopalse, in different kinds 

 of sense organs. 



A, B, sense rods of tactile hairs of cerci of Gryllus campestris 

 (Sihler, 1924). C, sense dome and rod of campaniform organ of Dytis- 

 cus marginalus (Hochreuther, 1912). D, dorsal scapel campaniform 

 organ and sense rod of halter of Syrphus (Pflugstaedt, 1912). E, 

 scolopala of halter of a fly (Pflugstaedt). F, scolopala from chordo- 

 tonal organ of wing base of a Lepidopteran, Cheiinatobia (Vogel, 1912). 

 G, scolopala of chordotonal organ of halter of Syrphus (Pflugstaedt). 

 H, optical longitudinal section of scolopala of tympanal chordotonal 

 organ of Acridium ccgypticiim (Schwabe, 1906). I, same as H, surface 

 view. J, cross-section through apical body {AB). K, cross-section 

 through middle of scolopala. L, cross-section through basal part of 

 scolopala. M, optical longitudinal section of scolopala of chordotonal 

 crest in. leg of Decticus vcrrucivoriis (Schwabe, 1906). 



Janet (1904) in the campaniform organs of ants. Vogel (1911) 

 describes sense rods in the campaniform organs of the wing bases 

 in Lepidoptera, which apparently closely resemble those of the sense 

 organs of the cerci in Orthoptera. Each rod, he says, has a pear- 

 shaped head containing a dark-staining apical body to which is at- 

 tached the end of an axial fiber from the sense cell, and the rod walls 

 have about ten internal rib-like thickenings. 



