XVII. A DEEP-SEA PRAWN, _Nematocarcinus undulatipes_. SLIGHTLY REDUCED. (_From Brit. Mus. Guide_) 128 XVIII. _Bathynomus giganteus._ ABOUT ONE-HALF NATURAL SIZE. (_From Lankester's "Treatise on Zoology," after Milne-Edwards and Bouvier_) 131 { _Latreillia elegans_, ONE OF THE DROMIACEA WHICH } { RESEMBLES A SPIDER CRAB. FROM THE MEDITERRANEAN. } XIX. { NATURAL SIZE } 155 { } { THE GULF-WEED CRAB, _Planes minutus_. SLIGHTLY } { ENLARGED } { THE MURRAY RIVER "LOBSTER," _Astacopsis spinifer_. } XX. { NEW SOUTH WALES. MUCH REDUCED } 177 { THE LAND CRAYFISH, _Engæus cunicularis_. TASMANIA. } { NATURAL SIZE } XXI. _Palæmon jamaicensis._ A LARGE FRESHWATER PRAWN OF THE FAMILY PALÆMONIDÆ. WEST INDIES. MUCH REDUCED 179 XXII. _Atya scabra._ A FRESHWATER PRAWN OF THE FAMILY ATYIDÆ, WEST INDIES. REDUCED 180 { THE RIVER CRAB OF SOUTHERN EUROPE, _Potamon edule_ } { (OR _Telphusa fluviatilis_). REDUCED } XXIII.{ } 182 { _Sesarma chiragra._ A FRESHWATER CRAB OF THE FAMILY } { GRAPSIDÆ. FROM BRAZIL. SLIGHTLY REDUCED } XXIV. _Æglea lævis._ SOUTH AMERICA. NATURAL SIZE 184 XXV. THE BLIND CRAYFISH OF THE MAMMOTH CAVE OF KENTUCKY, _Cambarus pellucidus_. NATURAL SIZE 186 { A WEST INDIAN LAND CRAB, _Gecarcinus ruricola_. } XXVI. { REDUCED } 190 { } { A LAND HERMIT CRAB, _Coenobita rugosa_. REDUCED } XXVII. THE COCONUT CRAB, _Birgus latro_. MUCH REDUCED 196 XXVIII. GROUP OF BARNACLES, _Coronula diadema_, ON THE SKIN OF A WHALE. JAPAN. REDUCED 209 { _Cymothoa oestrum._ AN ISOPOD PARASITE OF FISH. } { SLIGHTLY ENLARGED } XXIX. { } 220 { _Sacculina carcini_ ATTACHED UNDER THE ABDOMEN } { OF A COMMON SHORE CRAB. REDUCED } XXX. THE "NORWAY LOBSTER," _Nephrops norvegicus_. ABOUT ONE-THIRD NATURAL SIZE. (_From Brit. Mus. Guide_) 240 XXXI. THE COMMON EDIBLE CRAB, _Cancer pagurus_. BRITISH. MUCH REDUCED 248