. The annals and magazine of natural history : zoology, botany, and geology . spiders are situated, as is wellknown, at tiie extreme posterior end of the abdomen, groupedmore or loss closely round the anal tubercle. In Liphistius 446 Mr. T. II. Savory on the Spider Llpliistius. the spiiuierettes aro placeil in the middle of the lower surface,a place which is obviously more closely allied to the normalposition of the abdominal appendages of the other spiders have six, or fewer, spinnerettes, whileLiphistius alone has eight. The significance of these factsneeds no emphasis. The se
. The annals and magazine of natural history : zoology, botany, and geology . spiders are situated, as is wellknown, at tiie extreme posterior end of the abdomen, groupedmore or loss closely round the anal tubercle. In Liphistius 446 Mr. T. II. Savory on the Spider Llpliistius. the spiiuierettes aro placeil in the middle of the lower surface,a place which is obviously more closely allied to the normalposition of the abdominal appendages of the other spiders have six, or fewer, spinnerettes, whileLiphistius alone has eight. The significance of these factsneeds no emphasis. The segmentation of the abdomen is equally part of the body is protected by a series of nine dorsal))lates of a leatliery consistency, a fact which points to a rela-tionship between the Araneaeand the Pedipalpi and suggests that these plates may not represent segmenta-tion, but that they may result from the division of a dorsalshield, such as is found in the Oonopida3 and the Tetra-blemma. This is one of the points which it is hard to solve Fiir. ProEle. in the absence of embryological knowledge ; analogy is aptto prove misleading, but the following arguments in favour oftheir primitive nature may be cited :— 1. The fossilized spider, Protolj/cosa, of the Carboni- ferous strata possesses a similar series of dorsalplates. 2. Some species of the genus Paratropis, one of the more generalized Therapliosa?, show vestiges ofnine segments in the abdomen of the adult. 3. Since the abdomen of such spiders as have been embryologically studied passes through a segmentedstage it is reasonable to suppose that the segmentedform is primitive, and on this account the dorsalshield of Oonopides is simply to be regarded ashaving, like the rest of the abdomen, lost itsmetamerism. Mr. T. II. Savory on the Sjuler Liphistius. 4-i7 ViMitrally the first ami second .se<Tnieiit3 of the abdomenare provided with phitea, which cover the aperturas of thereproductive system an
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