620 PK0CEED1N08 OF THE NATI02fAL MUSEUM. vol. 57. 



conspicuously sculptured with unpaired median protuberance. Epi- 

 cranium dorsally and posteriorly obliquely wrinkled, otherwise 

 smooth; anterior margin of hypostoma concave. Ocellus small, close 

 behind ventrolateral margin of antennal ring. Basal, second, and 

 apical antennal joints proportioned as 1-|:3:1; supplementary joint 

 small; basal connecting membrane elongate, cylindrical. Mandible 

 plump, as long as wide, length about three-fourths of frontal suture; 

 apex blunt, not projecting over inner corner of mandibular base; 

 retinaculum hardly developed; one tiny, rounded tooth present be- 

 low apex; two very short and fine mandibular setae. Maxilla with 

 cardo and stipes basally covered by a comparatively large chitiniza- 

 tion; length of basal, second and apical joints of maxillary palpus 

 proportioned as 2:1:1; palpiger jointlilve, chitinized. Gula poorly 

 chitinized, as long as frons and as long as maxilla. Submentum and 

 mentum poorly chitinized. Stipes labii chitinized; length of basal 

 and apical joints of labial palpus proportioned about as 1:1. Pro- 

 thorax anteriorly about as wide as head, posteriori}'- somewhat wider, 

 about two-thirds as long as wide, somewhat longer and narrower than 

 the following thoracic segments; dorsally chitinized, no distinctly 

 defined thoracic shield; no distinct sternal plate. Meso- and meta- 

 thorax slightly or not chitinized dorsally. Legs poorly chitinized, 

 rather short. Abdomen with well-developed ampullae on second to 

 seventh abdominal segments ; lateral areas swollen. No definite basal 

 plate of cerci; the whole dorsal surface of ninth segment slightly 

 chitinized, posteriorly with grainlike asperites. Cerci short, straight 

 proximally fused, distally divergent, apically bifid. Mesothoracic 

 spiracles twice as large as the abdominal ones. 

 The systematic position of the present genus is isolated. 



PEIOCERA CASTANEA Newman. 



U. S. Nat. Mus., Wash., D. C. ; Specimen labeled " Priocera castanea in 

 white oak log with Lymexylon, Va., shore opp. Plnmmer's Island, Md., July 

 25, 1909; adults bred last year and also collected on same log this year." 

 H. S. Barber. Coir. 



(Figs. 14, 28, 41, 61, 76, 98, 110.) 



Total length, 13 mm.; extreme width, 2J mm.; extreme thick- 

 ness, 2,^ mm.; anterior width of prothorax, 2 mm. Mandibles, epi- 

 stoma, endocarina of frons, end of cerci Roman sepia ; remainder of 

 head capsule and tropin, antennae, prothoracic shield, and tarsi 

 from brown ocher to pale cadmium yellow; membranous parts 

 whitish. Setae fine, short, and whitish; numerous on chitinized. 

 sparse on membranous parts. Two mandibular setae. 



Subfamily D (pp. 620-622). 



Frons posteriorly limited by an acute angle. Epicranial suture 

 present, short. Second antennal joint small, about as long as apical 



