144 PROCEEDINGS OF THE NATIONAL MUSEUM 



Tergites black. Pygidium in male narrowed to an emarginate apex 

 in apical third; in female, triangular. 



Ventral segments: All black or very dark brown. Usually no trace 

 of luminous organs, but one male had the last ventral medially pink 

 with pink rudimentary luminous organs laterally. 



Legs dark brown to black. Claws simple. 



Aedeagus as in figure 2. 



Pyractonema depressicornis Gemminger and Harold 



Figure 4 



Pyractonema depressicornis Gemminger and Harold, Cat. Col. Des. Syn. Syst.' 



vol. 6, p. 1639, 1870. 

 Pyractonema compressicornis Solier, in Gay, Hist. Fisc. Pol. Chile, vol. 4, Zool., 



p. 446, 1849. 



Material: 35 males and 2 females. 



General: A large, probably nonluminous lampyrid, with etytra 

 bordered yellow. 



Dimensions: Males 11.5 to 18 mm. long by 3.5 to 7.0 mm. broad; 

 average 15.0 by 5.0 mm. Females 12.5 to 14.5 mm. long by 3.5 to 

 4.25 mm. broad. 



Pronotum with lateral margins slightly reflexed, apical margin 

 somewhat more so. Black except for two subrectangular red spots 

 occupying about 0.3 of total area. Disc not deeply channeled if at 

 all so, sometimes with a low carina in basal half. About 0.8 as long 

 as wide. Outline nearly semicircular, except for slight apical pro- 

 longation, less marked in females. 



Scutellum and mesonotal plates black. 



Elytra long, parallel or subparallel, usually tricostate. Black with 

 pronounced yellow lateral and apical borders about 0.2 of elytra! 

 width. No sutural border. Very narrow explanate margins. Sparsely 

 hairy. 



Head with frons black, slightly prominent in front. Eyes small, 

 width across them about 0.6 of pronotal width. Clypeus short, 

 black, tridentate. 



Antennae long, up to 0.75 of body length, shorter in females. Arti- 

 cles 3 and 4 shorter than 5 to 11. Short appressed vestiture with 

 scattered longer brown hairs on edges. 



Tergites all black with pronounced posterolateral projections on 5 

 to 7. Pygidium projects beyond the elytra in the female. 



Ventral segments: All black, except small reddish, lateral, rudi- 

 mentary (?) luminous organs on segment 8 in the male. These 

 organs are smaller in the female and mostly hidden under the 7th 



