36 J. L. LECONTE, M. D. 



(xroup 3. — LampijreH. 

 A sufficient character for separating this tiroup is found in the last 

 joint of the antennaj which is usually appendiculate, rarely {P/eofomm) 

 sinuate near the tip. The joints of the antennse vary in number as well 

 as form. The sexes are dissimilar ; the 9 is frequently larviform with 

 very short scale-like elytra ; the light organs seem to be always brilliant 

 in the 9, but variable in the S , sometimes well developed {Phausis 

 reticulata) sometimes wanting (P. inaccensa). The eyes of the % are 

 very large, contiguous or nearly so, both above and beneath. In the $ 

 they are moderately large (Fleotomus) or very small {Microphotus). 



Antennte bijDectinate, 14-jointed, very short and compact in tlie 9; eves moder- 

 ately large in 9 > very lai-ge and nearly contiguous in % ; 9 with very short 

 distant elytia PLEOTOMUS. 



Antennae simple, with quadrate joints ; eleventh joint with an articulated aci<'ular 

 appendage; 9 with short elytra; prothorax with transparent sjiots FHATJSIS. 



Antennae short, simple, with quadrate joints; 9-jointed {%), or 8-jointed ( 9 ) j 

 eyes very large, contiguous ( % ), very small, transverse, distant ( 9 ) : elytra of 9 

 very short, lounded ., MICROPHOTUS. 



PHAUSIS Lee. 



This genus is not sufficiently distinct from the European Lampnih'mi 

 jMotsch., and in fact the European species seems to have been naturalized 

 in ^Maryland and Illinois. The last dorsal segment is deeply emarginate 

 in the S , with acute angles ; the transparent prothoracic spots are very 

 distinct in % , but nearly wanting in 9 . The latter sex in F. reticulata 

 has elytra about as long as in Phot, xcintillans. 



Fifth and sixth ventral segments yellow, luminiferous 2. 



Ventral segments piceous, without light organs ; elytra less strongly reticulate {%,); 



6 mm.; Marquette, Lake Superior 3. iiiacceili^a. 



2. — Prothorax wider than long, elytra densely punctured ] {%) S..3 mm. ; Md. ; 111. 



1. spleudidiila. 

 Prothorax not wider than long, very obtuse in front, elytra confusedly reticu- 

 late, long in '^, short in 9; 9 elytra short, not longer than metathorax; 

 dehiscent, rounded at tip; 5.5 mm.; Ga. ; Tenn.; Tex 2. reticulata. 



]»IICROPHOTlIS Le,. 



The prothorax is very obtusely rounded in front, not carinate and 

 without transparent spots; the elytra £ are somewhat dehiscent and 

 rounded at tip ; the discoidal costae are distinct and the surface granulato- 

 punctate. Antennge very short in % , ten-jointed, not extending across 

 the eyes which are prodigiously large ; 9 larviform, antennaj still shorter, 

 nine-jointed, elytra small, distant, scale-like. 

 Body oval, elytra rounded on the sides; % 6—10 mm.: 9 unknown; Cape San 



Lucas, L. Gala dilatatu!4 Lee. 



Body elongate, elytra with parallel sides; % 6 — 10 mm.; 9 s— 10 mm.; Cala. ; 



'^'■•j Col aiigiistiis Lee. 



