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Show 742 MR. R. I. POCOCK ON ETHIOPIAN SPIDERS. [June 15 Family THERAPHOSID.E, Thorell (sensu stricto). The classification of the large Spiders referred to in text-books as 'Mygale' and known at the present time to systematists as Avlcularlldce or Theraphosldce, has hitherto proved to be a task of great difficulty and can as yet by no means be regarded as definitely settled. It is needless now to enumerate in detail the steps by which our knowledge of the group has been built up, and to trace the gradual appreciation of the value of characters for grouping the genera into natural assemblages. For practical purposes it will be sufficient to refer back no further than 1892, that is to say to Mons. Simon's latest classification \ which is a modification and an extension of the one propounded twenty years earlier by Dr. Anton Ausserer2. Simon classifies the Aviculariinae ( = Theraphosidae, Thorell, as adopted by me) as follows :- a. Scopulae * of at least the posterior tarsi divided by a line of bristles. a'. Tarsal scopulae of all the legs divided Ischnocolem. b'. Tarsal scopula? of 1st and 2nd legs undivided. a2. Tarsal scopulae of 3rd and 4th legs divided Chcetopelmatecs. b2. Tarsal scopula of 4th leg only divided. a3. Legs armed with numerous spines Crypsidromece. b3. Legs without spines, except on the tip of the protarsi Phlogiece. b. Tarsal scopuke of all the legs undivided. a*. Legs without spines, or at most a few. a5. Tarsi and protarsi narrower ; generally spines at the tip of the protarsi; thoracic fovea generally semilunar Selenocosmiece. bs. Tarsi and protarsi wider ; legs not spined ; fovea not semilunar. ae. Thoracic fovea minute ; anterior legs longer than the posterior Pcecilotheriece. bG. Thoracic fovea large and deep; posterior legs longer than the anterior Aviculariecs. 6*. Legs with many spines. a7. Posterior femora internally scopulate ; protarsus of 4th pair not scopulate Theraphosece. b1. Posterior femora not scopulate ; protarsus of 4th leg with small scopula. a9. Protarsus of 1st leg thickly scopulate to the base and usually without basal spines Eurypelmatece. bs. Protarsus of 1st leg with scopula not reaching the base; with basal spines Homceommatem. * ' Scopula' is the term applied to the pad of velvety hairs that clothes the tarsus and sometimes the protarsus of the appendages. Thus Mons. Simon's system rests primarily upon the presence or absence of a divisional line of setae upon' the tarsal scopulae. But when discussing the value of the character as applied both to genera and groups of genera, I have elsewhere3 remarked :-"If 1 Hist. Nat. Araignees, i. p. 132 (1892). 2 Verh. z.-b. Wien, 1871, pp. 122-224, also op. cit. xxv. 1875, pp. 125-204. 3 Ann. Mag. Nat. Hist. (6) xvi. p. 228 (1895). |