2IO Annals Entomological Society of America [Vol.1, 



sequence established earlier. The old family Atypidae was char- 

 acterized by the elevated position of the anal tubercule, the 

 normal number of the spinnerets being six (the genus Brachy- 

 bothrium excepted) , and the lower border of the chelicerae being 

 narrow and without a distinct groove for the reception of the 

 fang. The famih^ as now limited, is distinguished by the great 

 development of the coxal lobe of the pedipalps, the four pairs 

 of sternal impressions, and the presence of a conductor on each 

 genital bulb of the male. The Brachybothriinae have no coxal 

 lobes on the pedipalps, no suggestion of a conductor on the 

 genital bulbs; but have a rake on the chelicerae, the thoracic 

 furrow is longitudinal, and the sternal impressions are four in 

 Brachybothrium, six in Atypoides. The Hexurinae have only 

 two sternal impressions and no rake, the thoracic pit is longi- 

 tudinal, there is a suggestion of a coxal lobe on the pedipalps 

 and the genital bulbs have a short spur, probably analogous to 

 the conductor of the Atypinae. 



The species which becomes of special interest in connection 

 with these groups of Simon's, is Banks' Atypoides californica. 

 The male of this species seems to be unknown to science, so I take 

 pleasure in reporting the finding of two males, October, 1907, in 

 the immediate vicinity of Stanford University. A casual com- 

 parison of these specimens with the drawings of the male of 

 Atypoides riversi Cambr., shows marked differences between the 

 two species, and a careful study of the facts at hand, shows the 

 necessity of the formation of a new genus to accomodate the 

 species described by Banks. The female of this species is quite 

 close in structure to the female of Atypoides riversi, having a rake 

 and six sternal impressions; but the thoracic pit is round, not 

 longitudinal. The male has a rake, the thoracic pit round, short 

 coxal lobes on the pedipalps, much as in Hexura, and also has a 

 conductor on each genital bulb, nearly the full length of the bulb. 

 How it differs otherwise from Atypoides will be discussed in the 

 proper place below. In truth, the female of Aliat^^pus, as the 

 new genus will be called, seems to merit a position nearer the 

 Brachybothriinae, while the male, in certain respects, belongs 

 rather between the Hexurinae and the Atypinae. Such a condi- 

 tion of aft'airs makes a readjustment of Simon's classification of 

 these forms worthy of consideration. The affinities of Aliatypus 

 toward Atypus, however, are thru "secondary sexual characters" 

 in the male, which, if of as little weight in classification as some 



