CONTENTS 



Page 



Introduction 1 



Measurements and abbreviations used 2 



The oxystomatous and allied crabs of America 4 



Analogous species on opposite sides of the continent 5 



Species on both sides of the continent 5 



Order Decapoda 6 



Key to subtribes of the tribe Brachyura 6 



Subtribe Gymnopleura . 6 



Family Raninidae 6 



Genus Raninoides 7 



Genus Ranilia 17 



Genus Lyreidus 21 



Genus Symethis 24 



Subtribe Dromiacea 27 



Superfamily Dromiidea 27 



Family Dromiidae 30 



Genus Dromia 30 



Genus Dromidia 32 



Genus Hypoconcha 44 



Family Dynomenidae 51 



Genus Dynomene 54 



Genus Acanthodromia 55 



Family Homolodromiidae 57 



Genus Homolodromia 58 



Genus Dicranodromia 59 



Superfamily Thelxiopeidea 61 



Family Thelxiopeidae 62 



Genus Thelxiope 62 



Genus Paromola 68 



Genus Homologenus 70 



Family Latreilliidae 73 



Genus Latreillia 73 



Subtribe Oxystomata 75 



Family Dorippidae 75 



Genus Ethusa 77 



Genus Ethusina 89 



Genus Cymonomus 96 



Genus Cymopolus 98 



Genus Corycodus 101 



Genus Cyclodorippe 103 



Genus Clythrocerus 109 



Family Leucosiidae 121 



Subfamily Ebaliinae 123 



Genus Ebalia 123 



Genus Liihadia 136 



Genus Speloeophorus 141 



Genus Uhlias 149 



in 



