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some species could be either split, entire, or onlypartially separated. Most later authors have rejectedit as a character of generic value. It is, however, ofvalue when used in conjunction with other charactersin delineating phylogenetic lineages. The stateof the metapeltidium appears consistent within atleast some groups of species. In the Protoschizomidaethe metapeltidium is divided in Protoschizomusand A. lucifer; it is entire in A. huitzmolotitlensis, A.srygius, and A. patei. The divided metapeltidium ofA. lucifer is considered to have been derived inAgastoschizomus.Setation of the abdominal tergites: This characteris fairly consistent in the family Hubbardiidae and isof some use in determining relationships. Megaschizominaehave a submarginal row of four anterior setaewhich is not found in other Hubbardiidae. Protoschizomidaefrequently have extra anterior setaebut these do not form a distinct row and are presumablynot homologous to the setae of Megaschizominae.The Hubbardiidae most frequently have two largeposterior setae on segments I-VII, with four setae onsegments VIII-IX. In some species of Hubbardiinaethe lateral setae on segment VIII are missing. Inother species there are multiple setae on one or moretergites. There is some variation in number of setae,but usually the extra setae are either unpaired orminute; where there is a question it is assumed thatthe typical number is the normal state. As alreadymentioned, the presence of microsetae on tergitesI-II is a synapomorphy for the order. Some"Schizomus" have lost some or all of the microsetae.When microsetae are present on tergite I, there arethree closely spaced (in a row) on each side of tergiteII. A derived condition occurs in A. patei wherethere are still three microsetae per side but they occuras a triad (one centered in front of pairs of microsetae).Tergite I contains two posterior setae inall protoschizomid species except A. srygius inwhich the setae are missing. Tergite II always hastwo setae in the Protoschizomidae as do some Hubbardiidae.Tergite III has four setae in the P. pachypalpusgroup, but two setae in all other protoschizomidspecies (character 26). This character state isunresolved on the ordinal level because members ofthe Hubbardiidae have two, four, and more thanfour setae. Tergites IV-VII have four setae in the P.pachypalpus group but vary in other groups andgenera, with both character states being present insome specIes.Setation of the abdominal sternites: In the familyProtoschizomidae there are always two rows ofsubmarginal setae on sternites IV-VIII and sometimeson IX in the females. In the males of the P.pachypalpus group the setae are scattered or at mostform two close-set highly irregular rows near theposterior margin of the sternites. In the only speciesof the P. sprousei group for which males are known,the anterior row of setae is situated near the middleof the sternite rather than near the anterior margin.Most species of Hubbardiinae have two irregularrows in both sexes. The apomorphic condition(character 27) is found in Agastoschizomus males,which have two distinct rows of setae.Width/length ratio of sternites IV-VII: There is ageneral decrease in the width/length ratio with increasedbody size. Even so, this character appears tobe useful in separating Protoschizomus from Agastoschizomus.The width/length ratio of sternite VI(character 28) is below 2.3 for Protoschizomus. Thisremains true even for the species of Agastoschizomusthat are smaller than the largest Protoschizomus.The ratio is greater than 2.3 in Agastoschizomusand the Hubbardiidae.Abdomen: In some species of Hubbardiinae(Hubbardia Cook, Stenochrus Chamberlin, and"Schizomus"), some segments of the abdomen maybe extremely elongate. This elongation does not occurin the Megaschizominae or the Protoschizomidae.Abdominal muscles (character 29): The Protoschizomidaeshare with the Uropygi and Amblypygithe presence of eight dorsoventral muscles.The Hubbardiidae have lost the posteriormost pair.All protoschizomids, except P. rowlandi, have4-6 ventral setae on segment X of the abdomen. Thederived condition, in P. rowlandi, is the occurrenceof two setae.Abdominal segment XII of protoschizomids generallyhas two dorsal setae. That of A. srygius arequite heavy and more spinose. The setae on male A.huitzmolotitlensis are very long and are extendedover the flagellum.The flagellum of some male Hubbardiidae(Hubbardia, "Schizomus", and Megaschizominae) isapparently (observation of preserved material only)carried with the posterior end up or arched forwardtowards the anterior end of the animal. Most Hubbardiinaeand protoschizomids apparently do nothold the flagellum up. The IX stemite and tergite ofsome Hubbardiidae are modified so that the flagellumcan be held up. These modifications include ashorter tergite IX than sternite IX length and archedand reduced ventral stemite.Female flagellum: The flagellum is divided byannuli or rings in most schizomids. The annuli canoccur as either thinnings in the cuticle or as breaks39