" " flagellum of, =25= _Trichoniscus_, 21, 22, 26 " characters of, 17, 18, 22 " _pusillus_, 22, 23, 24, 25, 44, Plate iii. " " description of, 22 " " flagellum of, =23= " _pygmaeus_, description of, 23 " _roseus_, 23, 25, 44, Plate v. " " description of, 24 " " flagellum of, =24= " _vividus_, 22, 25, 44, Plate iv. " " description of, 23 " " flagellum of, =24= Tubes for specimens, 16 _Typhloniscus steinii_, 30 _vividus, Trichoniscus_, description of, 23 _vulgare, Armadillidium_, description of, 41 Walking legs, 4, 5 Webb, Mr. Wilfred Mark, 20, 25, 26, 35, 36, 45 Welsh names for Woodlice, 16 Westwood, Bate and, 17, 19, 30 White arsenic for destroying Woodlice, 14 Willmott, Miss, 45 Wood-ants, 15 Woodlice, in captivity, 12 " methods for getting rid of, 24 " position of, 1 " storage of specimens, 16 " Welsh names for, 16 Woodlouse, common, 4 Yolk, food, 10, 11, inset facing =10= _Zia agilis_, 21 " _melanocephala_, 29 $ LIST OF PLATES. PLATE _Ligia oceanica_ Linné I. _Ligidium hypnorum_ Cuvier II. _Trichoniscus pusillus_ Brandt III. _Trichoniscus vividus_ Koch IV. _Trichoniscus roseus_ Koch V. _Trichoniscoides albidus_ Budde-Lund VI. _Haplophthalmus mengii_ Zaddach VII. _Haplophthalmus danicus_ Budde-Lund VIII. _Oniscus asellus_ Linné IX. _Philoscia muscorum_ Scopoli X. _Philoscia couchii_ Kinahan XI. _Platyarthrus hoffmannseggii_ Brandt XII. _Porcellio scabier_ Latreille XIII. _Porcellio pictus_ Brandt and Ratzeburg XIV. _Porcellio dilatatus_ Brandt XV. _Porcellio rathkei_ Brandt XVI. _Porcellio laevis_ Latreille XVII. _Porcellio ratzeburgii_ Brandt XVIII. _Metoponorthus pruinosus_ Brandt XIX. _Metoponorthus cingendus_ Kinahan XX. _Cylisticus convexus_ De Geer XXI. _Armadillidium nasatum_ Budde-Lund XXII. _Armadillidium vulgare_ Latreille XXIII. _Armadillidium pulchellum_ Zencker XXIV. _Armadillidium depressum_ Brandt XXV. [Illustration: _PLATE I._ LIGIA OCEANICA Linné. THE QUAY-LOUSE. _Length, two to three centimetres._ Charles Sillem, del. ad nat. F. W. Reader, sculpt.] [Illustration: _PLATE II._