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Smuioval County: Ellis Cave, under rock nearrodent feces, 3 August 1976 (W.C. Welbourn), 1female.Dinocheirus te.xanus Hoff and ClawsonDinocheirus te.xanus Hoff and Clawson, 1952:27,figs. 16-19; Hoff, 1958:28.This species was described from 2 small collectionsfrom nests of Neotoma micropus Baird atLaguna Madre, Cameron County, Texas.Present material consists of a single male fromBFS Cave, Uvalde County, Texas, 8 June 1985 (A.Grubbs). This specimen is a little larger than thosedescribed by Hoff and Clawson but otherwise isvery similar.Dinocheirus venustus Hoff and ClawsonDinocheirus venustus Hoff and Clawson, 1952:31,figs. 20-23; Hoff and Bolsterli, 1956: 174; Hoff,1958:28. .?Acuminochernes sp.: Reddell, 1970:403.?Dinocheirus sp.: Reddell, 1970:403.Dinocheirus venustus was originally found in apack-rat (Neotoma) nest at Lawrence, Kansas (Hoffand Clawson, 1952). It was subsequently reportedfrom Iron County, Missouri, with no ecological data(Hoff and Bolsterli, 1956). The present record extendits range far to the west.The original description by Hoff and Clawson,supplemented by data in Hoff and Bolsterli, characterizethe species very well. However, a few pertinentadditions and comments may be made here,based on 23 mounted specimens (11 males, 12 females).The new specimens, all from caves inTexas, are on average a bit larger and have somewhatmore slender appendages than those reportedfrom Kansas and Missouri. There are 2 distincttransverse furrows on the carapace; no eyes evident.Male anterior genital operculum with 20-32 setae,including 4 long ones; posterior operculum with19-27 setae on face and 2-3 very small setae on eachside of middle of anterior margin; internal genitaliafairly large and heavily sclerotized. Female anteriorgenital operculum with 15-24 setae, posterior operculumwith 11-15; spermathecae are long, slendertubes without any terminal enlargement. Cheliceralhand with 5 setae, bs always acuminate, sbs usuallyterminally and subterminally denticulate but sometimesacuminate; flagellum of 4 setae. Palp of malegenerally heavier than that of female: male femur2.3-2.75 (female 2.35-3.0), male tibia 2.05-2.35(female 2.1-2.4), and male chela (without pedicel)2.05-2.5 (female 2.45-2.75) times as long as broad;male hand (without pedicel) 1.2-1.35 (female1.4-1.6) times as long as deep; male movable finger0.95-1.01 (female 0.93-1.00) as long as hand. Maleleg IV with entire femur 3.5-3.9 (female 3.65-4.0)and male tibia 4.8-5.5 (female 4.8-5.5) times aslong as deep. Tarsus of leg IV with short, acuminate,tactile seta 0.72-0.79 length of segment fromproximal end.Measurements (mm).-Ranges given first formales, followed in parentheses by those for females.Body length 2.42-3.32 (2.77-3.55). Carapace length0.795-1.00 (0.83-0.96). Palpal femur 0.70-0.89(0.63-0.86) by 0.275-0.35 (0.265-0.32); tibia0.57-0.79 (0.59-0.73) by 0.275-0.36 (0.28-0.32);chela (without pedicel) 1.12-1.36 (1.08-1.30) by0.49-0.615 (0.415-0.495); hand (without pedicel)0.585-0.76 (0.61-0.70) by 0.485-0.62 (0.415-0.49);pedicel length about O. 10; movable finger length0.59-0.72 (0.51-0.695). Leg IV: entire femur0.66-0.80 (0.67-0.79) by 0.175-0.23 (0.175-0.215);tibia 0.55-0.695 (0.565-0.65) by 0.11-0.13(0.105-0.13).New records.-TEXAS: Comal County: BrackenBat Cave, 19 January 1963 (J. Reddell and D.McKenzie), 1 female (JCC). Edwards County: DeepCave, 1,4 mile E Punkin Cave, 4 September 1965 (1.Reddell and D. McKenzie), on guano in upper levels,1 female; Devil's Sinkhole, 8 mi. NE Rocksprings,14 February 1965 (J. Reddell), 1 male, 1female; 14 March 1966 (1. Reddell), "under rockson guano and silt below the cave entrance," 1 male,4 females; 8 March 1968 (J. Reddell), 1 male.Medina County: Weynand Cave, 2 August 1965 (1.Reddell and J. Fish), 1 male. Val Verde County:Fern Cave, 14 April 1973 (T.R. Mollhagen), 16males, 12 females, 3 tritonymphs.Remarks.-Because of the acuminate form ofseta sbs on the cheliceral hand of some, these specimenswere at first thought to belong to the genusAcuminochemes (hence the tentative identification ofthe Deep Cave specimen in Reddell, 1970). Furtherstudy, however, has shown their similarity to Dinocheirusvenustus. The variability in the denticulationof sbs here raises a question about the distinctnessof Acuminochemes and Dinocheirus. Additionally,though, the absence of terminal enlargementsof the spermathecae sets this taxon apart fromboth Dinocheirus and Acuminochemes, where terminalenlargements of spermathecae were consideredthe rule. These problems further point up the needfor a thorough revision of the genera Dinocheirus148