652 Pomona College Journal of Entomolooy 



Key to Families of the Suborder Geophiloidea 



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



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



several pectinate lamellae. Family Himantariidae 



bb. Antenna 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 lamellse. 



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



entirely separate from each other; pleurae of prehensorial segment 



exposed each side of basal plate. 



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



several pectinate lamellse. Family Mecistocephalidae 



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



pectinate lamellae. Family Arrupidae fam. nov. 



1)1). Mandible with but a single pectinate lamella ; coxae of first maxillse 



fused with each other at least proximally ; pleura; of prehensorial 



segment not exposed each side of basal plate. 



c. Labrum entire, uniformly chitinized, coalesced with the cephalic 



plate excepting at ends ; hypopharynx strongly developed ; palpi 



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



V amily Tarnpiyidae 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 chitinized 



teeth ; chitinous lines of prosternuni well developed. 



Family Soniphilidae 



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



two teeth conspicuously larger and more strongly chitinized 



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 

 antennae arc filiform. The prehensorial feet are strongly developed and much 

 exj)osed 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 

 lamellae but no truly dentate plate. The coxse of the first maxilla' remain entirely 

 distinct. No suprascutella or plates between tergites and spiraculiferous sclerite 

 are present. The coxopleura? are pierced with numerous pores which are mostly 



