342 SCIENCE PROGRESS 



perhaps be attributed to the printer. The tangle of nomenclature may entrap the 

 most careful, and it is merely an unlucky slip that the only example given of the 

 genus Hippolyte (p. 164) is the type-species of the previously mentioned Virbius ; 

 but it is less excusable to find that Sir Ray Lankester's figure of Cymonomus 

 normani, copied on p. 185, is labelled C. granulatus, although the distinguishing 

 characters of the two forms are given on the next page, with the added error that 

 C. normani is said to come from the " East African Coast " instead of the North 

 Atlantic. Still more astonishing and altogether inexplicable are the statements 

 that in the crab Ocypoda "the gills have entirely disappeared" (p. 194), and that 

 " Crangon antarcticus occurs at the two poles and apparently not in the interme- 

 diate regions" (p. 200). Some of the figures illustrating this section are excellent, 

 but a few, notably the diagram of a Cirripede on p. 96, are very poor. 



The chapters dealing with the Trilobites and Eurypterida are by Mr. Henry 

 Woods, and give very full and well-illustrated accounts of these important fossil 

 groups. Mr. Woods dissents from the view, adopted by Sir Ray Lankester 

 among others, that the Trilobites are specially related to the Arachnida, and he 

 regards them as approximating to the primitive stock of the Crustacea. 



A brief " Introduction to Arachnida" and sections dealing with the King-Crabs 

 (Xiphosura) and with those curious and degenerate groups the Tardigrada 

 (" Water Bears ") and Pentastomida, are written by Mr. A. E. Shipley, who has 

 brought together a great many interesting details which the student will look 

 for in vain in the ordinary text-books. In discussing the King-Crabs the author 

 refers to, but does not adopt, Pocock's classification, objecting to the disappearance 

 of the name Limulus and also to the subdivision into genera and sub-families of 

 a group containing so few species " differing ititer se comparatively slightly." 

 It may be suggested, however, that questions of classification are not necessarily 

 connected with those of mere nomenclature. Many zoologists will applaud Mr. 

 Shipley's defiance of the "priority purists " in retaining the familiar name Limulus; 

 but it is important to have a classification which draws attention to the significant 

 fact that the Oriental King-Crabs are more nearly related to one another than they 

 are to the American species. 



The air-breathing Arachnida (Scorpions, Spiders, Mites, and the like) are 

 dealt with by Mr. Cecil Warburton. Three of the seven chapters in this section 

 are devoted to the spiders, and provide, what has long been wanted, a tolerably 

 full summary of what is known of the habits and classification of these attractive 

 animals. A long account is given of spiders' webs and nests, and the varied 

 methods of their construction — a subject to which the author has previously made 

 noteworthy contributions. The chapter on the classification of spiders, largely 

 based on the work of Simon, will not escape criticism, especially since the author 

 adopts no divisions of higher rank than families, regarding those wider groups 

 which have been proposed as " not of great importance." 



The other Orders of Arachnida are dealt with more briefly, and in some 

 respects the accounts given of them are hardly up to date. Thus, no mention is 

 made of the stridulating organs possessed by many Scorpions, and the section 

 dealing with the Pedipalpi (Whip- scorpions) seems very insufficient. The author 

 does not appear to have consulted the important memoir on the Tartarides, 

 published in 1905 by Hansen and Sorensen, otherwise he would hardly have 

 stated that the carapace in this group is " two-jointed " (p. 310) or that the species 

 are found only in Burma and Ceylon (p. 312). No authority is given for the name 

 GraephonKs mentioned on p. 309 as that'of a fossil Tarantulid, and we are there- 

 fore left to conjecture what may be its relation to the better-known Geraplirynus. 



