REVIVAL OF AN EARLIER VIEW 147 



ferred. The Anomoura are not distinguished from the 

 Brachyura and Macroura by any common character ; from 

 the former they differ by the disposition of the vulvee, 

 from the latter by not having a fan-shaped termination to 

 the pleon. But all the organs vary extremely in the 

 Anomoura, and no bond of connexion between the Apte- 

 rura and Pterygura is found either in the shape of the 

 antennae, mouth, maxillipeds, trunk, plastron, branchiae, 

 or in that of the pleon. The Anomoura contain forms 

 which differ more from one another, than the Brachyura 

 do from the Macroura. By the Anomoura the closest re- 

 lationships are torn asunder, as the Dromiacea from the 

 Maiacea, the Raninoidea from the Leucosis, the Porcel- 

 lanidea from the Galatheae, the Megalopidea from the 

 Astacoidea.' 



This criticism, published in 1841, appears now to be 

 winning deserved acceptance. The recent researches of 

 M. F. Mocquard into the armature of the stomach also 

 show the Anomura to be an artificial division. With the 

 transfer of the Pterygura to the Macruran sub-order, in 

 which all the families are pterygurous, the name becomes 

 inappropriate and may give place to the older name 

 Anomala, used by Latreille, though in a narrower applica- 

 tion. Any slight inconvenience that may result from the 

 similarity of name between the Brachyura anomala and 

 Macrura anomala will be compensated by the reminder 

 thus supplied that these two tribes correspond with the 

 collective Anomura of Milne-Edwards. 



The Macrura contaia the following tribes : — Anomala, 

 Thalassinidea, Scyllaridea, Astacidea, Stenopidea, Penaei- 

 dea, Caridea, among which will be found along with others 

 those popularly well known as Hermit Crabs, Lobsters, 

 Crayfishes, Prawns, and Shrimps. 



The following Table shows the subdivision of the tribes 

 into legions and families : — 



