660 Pomona College Journal of Entomology 



of prclicnsorial fVtt vi-ry large (sec figure). Spiracles all circular, the first 

 not visibly larger tliaii the second. I.ast ventral plate very wide, strongly 

 narrowed eaudad. Coxopleurif with numerous small pores and usually on two 

 larger ones, all arranged along and lieneath the edges of the ventral plate. In 

 immature specimens often only the two larger ])ores on each side evident. Anal 

 legs in female slender, about eciualling the jjenult in length, ending in a long 

 claw; in the male greatly enlarged and flattened dorso-ventrally. In the Cali- 

 fornian specimens examined the number of pairs of legs varies mostly from 

 sixty-nine to seventy-five but often falls to sixty-seven and may be as large as 

 ninety-one, as in a sjjecinien from Oroville. 



I ha\e seen s))ecimens from the following localities: Oroville, Pacific Grove, 

 Berkeley, Stanford and Santa Barbara (author's collection), and from Clareniont 

 (Prof. Baker). 



Subfamily Chilenophilinae 

 ( Ribautiina of Brolemann) 

 This recently established subfamily is proving to be a large one, a con- 

 siderable number of genera now having been found to belong to it. The group 

 is readily distinguished by characters of the second maxillae, these having the 

 two halves of the coxosternum almost separated at the middle and each presenting 

 a very conspicuous, strongly chitinized suture extending from the caudo-external 

 angle meso-cephalad. Three genera are represented in California. 



Key to Genera 

 a. Side pieces of labrum extending over the middle one and meeting at the 

 median line ; and legs ending in a strongly developed claw. 



Genus Gnafhomerium Ribaut 



aa. Side pieces of labrum completely separated by the middle one ; anal legs 



clawless or ending in a rather weakly developed claw. 



b. Femur of paljjus of second niaxilhe with a distinct process at distal 



meso-dorsal angle ; anal legs ending in a small membranous seventh 



article which replaces the claw. Genus JVatophilus Chamberlin 



bb. Femur of palpus of second maxillae with no such process ; anal legs 



with but six joints and clawless or with a weak claw. 



Genus Taiyuna gen. nov. 



Genus Gnathomerium Ribaut 



This genus is represented in North America by several species of which one 

 is known to occur in California. A second species, G. utahensis Chamberlin, 

 common in Utah, may range into the mountains of this state. 



The species of this genus are ty])ieally widest anteriorly and attenuated from 

 the head eaudad. The lateral i)ieees of the labrum extend mesad over the middle 

 piece and are contiguous with each other at the middle line, tlie edge of tlie middle 

 piece bearing teeth which ))roject out from beneath, the lateral pieces fronged 

 with jiectina?. Palpus of second maxilla triarticulate, all articles lacking special 

 jiroeesses. Ventral pores not in definite areas. The anal legs consist of tlie 

 usual six articles, the ultimate ending in a well developed claw. 



