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Protoschizomus is considered a derived condition inthe Protoschizomidae (character 22). The trochanterin the Uropygi can be slightly produced or not.When slightly produced, it is widened as well andnot laterally compressed as in schizomids. We believethe slightly "produced" state in the Uropygiarose independently and is not homologous with theproduced state in the Schizomida.The pedipalpal trochanter has a spur on the mesalside in most Hubbardiidae. However, the spur is absentin some apparently unrelated genera in theHubbardiinae. It is absent from all Protoschizomidaeand Uropygi and its presence in the Hubbardiidae istentatively considered to be a synapomorphy. Apparently,the spur has been secondarily lost (or derived)on several different occasions in the Hubbardiinae.Further studies, with emphasis on the occurrenceof the mesal spur, are needed to confirmthe polarity of this character.Basitarsal-tarsal spurs on pedipalp (character 23):The spurs on the protoschizomid pedipalp are symmetricallyplaced with respect to the claw. InMegaschizominae they are slightly asymmetrical,whereas in the Hubbardiinae they are distinctlyasymmetrical.Spinose-setae on pedipalps: One of the charactersused by Rowland (1975b) in defining the Protoschizomidaewas the presence of thick "spines" withsocketed bases on the pedipalp (see materials andmethods on terminology). This character is, however,also shared by Megaschizomus, Trithyreus,and Schizomus ashmolei Reddell and Cokendolpher.There is a complete gradation between hair-like setaeand spinose setae and it is obvious that spinosesetae are only modified setae. The absence of rigidspinose setae on most species of Hubbardiinae,however, implies that the character is of some phylogeneticsignificance. All species of Protoschizomusand Agastoschizomus possess spinose setae onthe tibia and some species also have spinose setae onthe patella. Protoschizomus gertschi also has spinosesetae on the femur. Megaschizomus mossambicus,Trithyreus, and Schizomus ashmolei have spinosesetae on all segments. Most protoschizomids (exceptA. patei, P. pachypalpus, P. rowlandi, P. sprousei,P. purificacion) have spinose setae on the patella.Because the resulting matrix does not follow anypattern observed with other characters, we assumethe difference between spinose setae and setae isminor.Anterior sternum: The number of setae is givenfor the anterior sternum, but this character is oflimited value even in species recognition. The presenceof only one sternapophysial seta occurs in A.patei. A single male of P. sprousei and the onlyknown specimen of P. treacyae also have a singlesternapophysial seta. All other species of Schizomidapossess two sternapophysial setae. The presenceof only one seta is therefore of considerable interestbut its phylogenetic significance is unknown since itoccurs in species apparently not closely related.Legs: The general increase in length and slendernessof the legs is almost certainly a troglomorphicadaptation. The epigean species (P. pachypalpusgroup) have legs I and IV shorter than the body,whereas all of the cave species have these legslonger than the body.Tarsus I: Agastoschizomus patei has the firstsegment of tarsus I longest, whereas it is approximatelyequal to or shorter than the last segment inall other Schizomida.Anterodorsal margin of femur IV: The anterodorsalmargin of femur IV slopes posteriorly in all Protoschizomidae,Megaschizominae, Trithyreus, andSchizomus ashmolei. In the remaining Hubbardiinaethe margin forms about a 90° angle.Length of femur IV (character 24): Femur IV isless than 4.8 times longer than deep in Protoschizomusand Hubbardiidae, but more slender in Agastoschizomus.This is probably related to the greaterspecialization to cavernicolous life by the latter species.The effects of the change in femur thicknessand associated musculature on the ability to jumphave not been investigated.Length of trochanter IV (character 25): TrochanterIV is about 1/2 the length of femur IV inMegaschizominae and Protoschizomus, and about1/3 the length in Agastoschizomus, Hubbardiinae,and Uropygi. We presume this condition arose separatelyin the two groups and therefore we have assignedseparate apomorphic states to those formswith longer trochanters.Mesopeltidial plates: The smaller species of Protoschizomidaeall have smaller plates, with the gapbetween them being greater. The increase in size ofthe plates and subsequent decrease in the gap appearsdirectly correlated with size and probablyprovides greater support to the larger species. It is,therefore, of limited value phylogenetically.The condition of the metapeltidium was originallyused to separate genera in the Hubbardiidae,with species having an entire plate being placed inSchizomus (and later Megaschizomus was added) andthose with a split plate being placed in Trithyreus.The value of this character for generic identificationwas questioned by Hansen and Sorensen (1905), althoughthey provisionally utilized it in separatingsubgenera. They noted that the metapeltidium in38