Chilopoda • 17 h 
dd Ventral pores present, these arranged in four areas. 
Nesidiphilus Chamberlin. 
cc No clypeal area present. (Distoectal angle of coxse of second maxillie prolonged.) 
d No ventral pores present; distoectal angle of tibia of second maxillie prolonged 
and strongly chitinized. Brachygonarea Ribaut. 
dd Ventral pores present; distoectal angle of tibia of second maxillae not thus 
prolonged. 
e Lappets present on first maxilte. Polygonarca Attems. 
ee No lappets present on first maxillae. Ribautia Brolemann. 
Cryophilus, n. gen. 
Frontal suture absent or very vaguely indicated. Prebasal plate not 
exposed, the cephalic overlapping the basal. Dorsal plates bisulcate. 
Antennae short, filiform. 
Clypeal area present, finely aerolated. 
Labrum free, tripartite. Median piece distinct and of good size but com- 
pletely overlapped and covered from below by the lateral pieces which are in 
contact at the median line. Lateral pieces fronged throughout with nume'-ous, 
closely arranged, long spinescent processes. 
Outer branch of first maxillae distinctly biarticulate; bearing two mem- 
branous lappets of which the distal one is the larger in the genotype. Inner 
branch undivided, set off by a suture. Coxae completely coalesced. Coxae 
of second maxillae weakly united at middle by a less chitinous isthmus; pleuro- 
sternal sutures strongly developed; pore mesad of anterior part of suture, opening 
through mesal edge of sclerite; palpus triarticulate, terminating in a large 
simple claw, none of the joints with processes. 
Prehensors large, exposed at the sides and projecting well beyond the front 
margin of the head. Claw armed at base; femuroid also armed and the inter- 
mediate joints with weaker teeth. 
Prosternum without chitinous lines. Anterior margin unarmed. 
No ventral pores present. 
Spiracles circular. 
Last ventral plate of intermediate width, sides converging caudad, trapezi- 
form. Tergite of last pediferous segment very broad, moderately narrowed 
and rounded caudad. 
Coxopleurae moderately inflated, not unusually elongate or exposed at 
sides of prescutum. Pores small and moderately numerous, mostly near edge 
of ventral plate. 
Anal pores present, small. 
Anal legs clawless; consisting of six joints beyond coxopleurae. 
Genotype: C. alaskanus, n. sp. 
This genus is undoubtedly close to Arctogeophilus, established as a sub- 
genus in Geophilus by Attems,^ but now obviously distinct from the latter in 
generic and in subfamily or family standing. Attems' figure of the maxillae 
of the genotype of Arctogeophilus, A. glacialis', shows the palpi of the second 
pair as quadriarticulate. a condition in which, if correctly represented, the 
species is unique. Prof. Ribaut segregates the genus Gnathomerium from 
Arctogeophilus on the assumption of the correctness of this figure.^ Aside 
from this character, with the doubt one can scarcely help feeling as to the exact- 
ness of Attems' j&gure, Cryophilus differs in the presence of distinct clypeal 
area, which is definitely denied to Arctogeophilus by its author. Also, the 
figure mentioned represents the segmental pore as enclosed on the mesal side, 
1 " Die Mvriopoden der Vega Exped.", Arkiv for Zoologi, 1909, 5, p. 23. 
2Loc. cit.; pi. 1, f. 2. 
^ " Sur un Genre Nouveau de la Sous-tribu des Ribautiina," Bull. Soc. d'Hist. nat. et de Sci. 
biol. de Toulouse, 1910, 43, pp. 105, 106. 
