6 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



on its ventral surface. The sides are membranous and the ven- 

 tral surface is more or less chitinized. The lateral lobes ar- 

 ticulate freely on the basal piece and are connected therewith 

 by the first connective membrane (1st con. mem.). The whole 

 aedeagus is connected with the body wall by the second con- 

 nective membrane (2nd con. mem.). The lateral lobes often 

 bear outwardly directed spines and anterior flabellae. The form, 

 number of spines and comparative length and shape of these 

 plates are remarkably constant in all the specimens in the vari- 

 ous species of Elateridae examined by the writer and are of de- 

 cided specific value. The terminology used in this paper is that 

 used by Sharp and Muir 1 in their excellent Memoire on the 

 male genital tube. 



The following table will serve to differentiate the four species 

 now recorded from North America as based upon the male genital 

 characters : 



A. Lateral lobes of genitalia with a median, outwardly, directed spine 

 in addition to the terminal spine (Plate II, fig. g). 



arizonicuH sp. riov. 

 AA. Lateral lobes without median spine. 



a. Sides of the lateral lobes parallel, suddenly constricted near 



outer fourth; median lobe without ridged depression on 

 upper surface (Plate II, fig. /) texniui* sp. uov. 



b. Lateral lobes gradually attenuated from base to tip, median 



lobe with prominently margined dorsal depression. 



1. Mediae lobe narrow as tip of lateral lobe (Plate IT, tig-. 



c, d, e) atlanticus sp. ivv. 



2. Median lobe twice as broad as tip of lateral lobe (Pl^e 



II, figs, a and b)..' physoderus Geri| 



Pyrophorus physoderus Germ. 2 



(Plate III, fig. c) 



v 



3 



"Piceus, fusco-pubescens, thorace suboblongo, convcxo. latcriluis an- 

 trorsum deflexo, maculis vesicularibus angularibus, antennis corporH 

 dimidio brevioribus, elytris punctato-striatis, apice muticis. Habitat na 

 Alabama Americae borealis (Gory.). 



"Dem P. pyralis verwandt, aber kleiner, dunkler braun. das Halsscliild 

 an den Seiten nach vorn tiefer herabgebogen, die Fiihlcr kiir/er und die 



5 



Deckschilde an der Spitze ungedornt. 



Jj 



1 The Comp. Anat. of the Male Gen. Tube in Coleo. Trans. Eni! 

 Toe. Lond. Part III, Dec. 24, 1912. || 



5 Zeit. f. d. Ent. Ill, p. 36, 1841. 



