652 Pomona College Journal of Entomology 



Key to Families of the Suborder Geophiloidea 



a. Mandible with a dentate lamella and with one or more pectinate lamellae. 



b. Antenna- flattened, broad at base and attenuated distad; mandible with 



several pectinate lamellae. Family Hhnantarndae 



bb. Antennie cylindrical, filiform, not broad at base and attenuated distad; 



mandible with a single pectinate lamella. Family Schendylidae 



aa. Mandible without any dentate lamella ; with one or several pectinate lamellae. 



b. Mandible with two or more pectinate lamellae; coxae of first maxillae 



entirely separate from each other; pleura; of prehensorial segment 



exposed each side of basal plate. 



c. Coxae of second maxilla? broadly coalesced at middle; mandible with 



several pectinate lamellae. Family Mecistocephalidae 



cc. Coxae of second maxillae entirely separate; mandible with but two 



pectinate lamellae. Family Arrupidae fam. nov. 



bb. Mandible with but a single pectinate lamella; coxae of first maxillae 



fused with each other at least proximally; pleura of prehensorial 



segment not exposed each side of basal plate. 



e. Labrum entire, uniformly ehitinized, coalesced with the cephalic 



plate excepting at ends ; hypopharynx strongly developed ; palpi 



of first maxillae thick, strongly arched together in a semicircle. 



FajnilyTampiyidae fam. nov. 



cc. Labrum free (in ours) ; tripartite, or with the divisions clearly 



traceable if secondarily coalesced; hypopharynx not unusually 



developed ; first maxillae not thus strongly arched in a semicircle. 



d. Median piece of labrum extending along surface of the lateral 



' with which it is fused at least in part; at middle the edge 



bears two conspicuously larger and more strongly ehitinized 



teeth; chitinous lines of prosternum well developed. 



Family Soniphilidae 



dd. Median piece of labrum entirely free, not bearing at middle 

 two teeth conspicuously larger and more strongly ehitinized 

 than those adjacent; chitinous lines absent or but weakly 

 developed. Family Geophilidae 



Family Mecistocephalidae 



In this family the cephalic lamina is long and relatively narrow. The 

 antennEB are filiform. The prehensorial feet are strongly developed and much 

 exposed at sides of head from above, the pleurae of the segment also being 

 distinctly exposed at the sides of the basal plate which is narrow. A prebasal 

 plate is never present. The labium is tripartite with the median piece very 

 narrow, its sides being parallel or nearly so. The mandibles bear several pectinate 

 lamellffi but no truly dentate plate. The cox» of the first maxillae remain entirely 

 distinct. No sujirascutella or plates between tergites and spiraculiferous sclerite 

 are present. The coxopleurae are pierced with numerous pores which are mostly 



