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PROCEEDINGS OF THE NATIONAL MUSEUM 



Figures 69-70. — Polyplax cannomydis, nev.' species: 69, Allotype 9 ; 70, Holotype cf. 



segments 3-7 with 1 or 2 lateral setae near paratergal plate on each 

 side. Paratergal plates as in male. Genitalia (fig. 72) not t3"pical of 

 Polyplax species. Genital plate (of segment 8) rectangular, lip of 

 vulva smooth, not beset with fimbriate processes; lateral setigerous 

 lobes of segment 8 ("gonopods") merely more heavily pigmented 

 areas occurring laterally on genital plate, not protruding as lobes, 

 with 2 or 3 setae on the pigmented area. Laterally, below vulva, 

 lobe on each side bearing many setae; below these, the usual lateral 

 setigerous lobes of segment 9 ("gonopods"). Spermatheca heavily 

 sclerotized, appearing as a ring-shaped sclerite. 



Lengths: Male 1.5 mm.; female 2.0 mm. 



The affinities of cannomydis, new species, are difficult to outline. 

 There is a very real question as to whether it belongs in Polyplax or 

 whether it should be segregated as the type of a new genus. The 

 female external genitalia of cannomydis are not of the usual Polyplax 

 type. In typical Polyplax the genital plate has a triangular median 

 sclerotization flanked by definite lateral setigerous lobes ("gonopods"), 

 and the tip of the vulva is always fimbriate to varymg degree (fig. 

 73). P. cannomydis has the setigerous lobes incorporated into the 

 genital plate and the lip of the vulva smooth. The well-marked 

 setigerous lobes occurring laterally between the vulva and the seti- 

 gerous lobes of the ninth segment are unusually well developed in 

 cannomydis, although typical Polyplax species do have groups of 

 setae in these positions. Not only are the female genitalia different 



