198 THE CANADIAN ENTOMOLOGIST 



Includes also the species described below. These forms are at once dis- 

 tinguishable from others by the peculiar male palpi which are notably fixed 

 in structure in comparison with other characters such as those of the cephalo- 

 thorax. 



Spirembolus vallicolens, sp. nov. 



Male.- — Carapace dusky over yellow, darker toward lateral margins. Legs 

 and palpi somewhat paler than carapace. Labium and endites in colour like 

 the carapace, the sternum darker. Abdomen blackish, without definite mark- 

 ings. Anterior portion of pars cephalica elevated but not bulging forward 

 over base of clypeus as it does in mojiticolens, the lower part of clypeus slanting 

 farther forward, the head in dorsal view not so convex anteriorly. The posterior 

 row of eyes is slightly procurved instead of a little recurved as it is in monticolens, 

 and the eyes are equidistant, though in the female the medians are obviously 

 more widely separated. Anterior row of eyes conspicuously procurved instead 

 of straight; median eyes much smaller than the laterals, nearer to each other 

 than to the laterals, but much less widely separated from the latter than in 

 monticolens in which the convexity carries the medians far forward. Palpus 

 very similar to that of monticolens; the tibial apophysis is more strongly and 

 uniformly curved than in the genotype, in the latter being comparatively straight 

 above the curving basal portion. See Fig. 21, 4 and 5. 



Female. — ^The form of the epigynum is shown in Fig. 21, 6. 



Length of male 1.85 mm. Length of cephalothorax .7 mm.; width .58 mm. 



Locality. — Utah: Mill Creek. A number of specimens secured by sifting 

 leaves in September. 



It will be noted that the less elevated and forwardly protruding head in 

 this form is associated with considerable differences in eye relations from those 

 in the genotype. 



Catabrithorax gen. nov. 



Much resembles Gongylidiellum in its broad cephalothorax with frons 

 much wider than the area occupied by the eyes. Clypeus lower than length of 

 median eye area, in the genotype much so. Anterior row of eyes straight or 

 but very slightly curved, eyes close together, typically less than their radius 

 apart, if any different the median eyes closer than to the laterals, median eyes 

 smaller than the laterals; posterior row of eyes straight, the eyes nearly equi- 

 distant, the medians being a little nearer each other than to the laterals. Area 

 of median eyes as wide as or a little wider than long. Anterior tarsi shorter 

 than the metatarsi. In the male palpus the tibia has above at anterior end on 

 mesal side a stout simple hook which curves ectad. The tarsal hook arising at 

 distal end of bulb, where it is stout, runs to base of bulb and then bends back 

 distad, this second part substraight, narrowing distad, unbranched, and free 

 from the bulb. Embolus issuing at distal end of bulb from a tube-like fold. 

 (Cf. Figs.) 



Genotype. — C. clypiellus, sp. nov. 



The structure of the male palpal organ is obviously different from that of 

 latehricola Cambridge, type of Gongylidiellum, and the tarsi of the legs are 

 shorter than the metatarsi. The close correspondence of the important features 

 of the palpal organ in the two species here tlescribed, while differences in such 



