I'VUUCHROIDAE 413 



TIjo species are numerous; the genera, except Tanartlirus, are 

 reinesented on the Atlantic district, but thut; I'ar no species of 

 Tunioderus has occurred in the raciiic region. The dilierences 

 between the third, fourth, and lifth genera seem ratlier indefinite. 

 Tanarthrus, besides the elongated 11th joint of the antennae, and 

 contiguous middle co.xae, is farther remarkable for having the elytra 

 shorter than the abdomen, and subtruncate at the extremity, 'llie 

 genus contains but three species, from the Colorado Desert and 

 Utah, one of which, T. salinus Lee., flies and runs on salt mud, 

 after the manner of a Cicindela. The species of Notoxus live on 

 flowers and leaves; those of Anthicus are very numerous; some 

 are found on plants, but the greater number live near the margin 

 of water, especially in sandy localities. Three species of Mecy- 

 notarsus occur, two of which are from the Atlantic region, the 

 other from California. 



Fam. LXX.— pyrochroidae. 



Mentnm trapezoidal, narrowed in front, supported bv a 

 large gular process; ligiila large, prominent, bilobed, labial 

 palpi 3-jointed. 



Maxillee with large exposed base, and two corneons ciliated 

 lobes; palpi 4-jointed, moderately dilated. 



Head somewhat inclined, strongly constricted a short dis- 

 tance behind the eyes, which are einarginate and not finely 

 granulated, and sometimes very large ; neck not very slender, 

 received in the thorax;- labrnm prominent; mandibles short, 

 emarginate at tip. 



Antennae inserted at the sides of the front just before the 

 eyes, 11-jointed; serrate or siibpectinate (9), and ramose (s); 

 rarely (Ischalia) nearly filiform. 



Prothorax narrower than the elytra at base, lateral siitnre 

 completely wanting; anterior coxal cavities widely open 

 behind, confluent. 



Mesosternum pointed behind; side pieces attaining the 

 coxal cavities, which are confinent; mctasternnm long, side 

 pieces narrow. 



Elytra wider than the abdomen, rounded at tip; cpiplenra3 

 almost wanting, visible only near the base. 



Abdomen with five free ventral segments; the 5th in the 

 male is emarginate, and the 6th is visible. 



