PSYCHE. 



ANTENNAL STRUCTURE OF CERTAIN DIPLOSIDS. 



BY E. PORTER FELT, ALBANY, NEW YORK. 



The antenna of the male Diplosis 

 is commonly said to possess twice the 

 number of segments as does that of 

 the female, excluding the two liasal 

 segments in each sex. At least such 

 has been the accepted number until 

 within a few jears. According to 

 Kieffer,* we owe the discovery that 

 these segments in the male are com- 

 pound and composed of two enlarge- 

 ments to Laboulb6ne, this, of course, 

 doing away with the disparity in nuin- 

 ber of antennal segments between the 

 sexes. In this same paper Kiefter 

 describes some novel structures found 

 upon the antennae of the male, which 

 he terms Jilels argues and which 

 perhaps may be translated as arched 

 Jilaments. 



The arched filaments difler widely 

 from ordinary setae, though they oc- 

 cur in whorls in the same manner. 

 They arise from pits in the chitine in 

 much the same way as do the setae, 

 but, instead of remaining single and 

 tapering to a point, they divide near 

 the base into two equal branches which 

 diverge to the middle of their length 

 where they recurve, sharply as a rule, 

 and turn to unite with the base of the 

 adjoining filaments in the whorl (Fig. 



* Bidl. sSances Soc, enioinol. Fr., iSgs, p. CXCII. 



i). Thus by means of tlie anasto- 

 mosises these arched filaments, which 

 from their designation one would 

 expect to be free from each other, are 

 in reality continuous and form a looped 

 thread around the segmenE with 

 anchoring branches at regular intervals. 

 This structure is well brought out in a 

 preparation of the male antennae of 

 Diplosis pyrivora Riley. In this in- 

 stance a number of the arched filaments 

 accidentally became loosened from 

 their attachments, but the anastomo- 

 sises, wliere each arch is joined to the 

 base of the next, remained unbroken 

 and distinct. In this preparation the 

 components of some of the arches may 

 be seen diverging at very various 

 angles — -another stiong fact in favor 

 of their being no connecting membrane. 

 The whorls of arched filaments occur 

 on both enlargements of the antennal 

 segments ; in some species one on the 

 basal and two on the medial enlarge- 

 ment. The ordinary setae occur in 

 whorls in close proximity to the arched 

 filaments, though usually nearer the 

 base of the segment, unless there be 

 two sets of filaments on one enlarge- 

 ment. The arched filaments have a 

 uniform diameter throughout their 

 course, though the anchoring Iiranches 

 are a little stouter; but there is no 



