316 On the Carcinological Fauna of the Caribbean Sea &c. 



The family Di-omlidee, hitherto so distinct from the Homo- 

 lidee, is now united therewith by the genus Homolodromia^ 

 the legs of which also ]-esemble those of Doripjie. The Acan- 

 thodromice are intermediate between the Dromice and the 

 Dynomenm ; they have the buccal pieces, the eyes, and the 

 antennge of the former, and the ambulatory feet of the second. 

 The Dicranodromue have the carapace narrower than that of 

 the ordinary Dromice ; its form resembles that of certain 

 fossil Crustaceans of the secondary formations, of which the 

 genus Ogydromites has been formed ; the legs are very long, 

 like those of the Homolo^. In Homolopsis also the body is 

 more rounded and narrower than that of the last-named Crus- 

 tacea ; and in this respect they approach the Droraiidie ; but 

 their eyes are nearly atrophied. The Homoloe are represented 

 by two species, one of which appears to me to differ in no 

 respect from //. spinifrons^ hitherto found only in the Medi- 

 terranean. Tliis is a fresh example of the immense geogra- 

 phical distribution attained by certain animals of the great 

 depths. Cymopolia^ of which one species also inhabits the 

 Mediterranean, possesses eight in the Caribbean Sea. Some 

 of them approximate to Dorippe by the intermediation of Gy- 

 clodorippe and Cymonomus ; and these last-mentioned crusta- 

 ceans, which are perfectly blind, have, on the other hand, close 

 affinities with the Ethusce. The genus Ethusa, supposed to 

 be confined to the Mediterranean, must also be recorded among 

 those of the American seas ; among the Crustacea from the 

 Florida reefs I have recognized a species and described it 

 under the name of E. ajuericana, only differing from E. inas- 

 carone by characters of but little importance. 



The examples just cited suffice to give an idea of the 

 interest attaching to the study of the animals from great 

 depths. These bathymetrical researches are only commencing ; 

 and when we compare the small extent over which the dredge 

 has been dragged with the immense spaces which have never 

 been touched, when we reflect upon the manifold causes 

 which render the retreats of certain animals still inaccessible 

 to our means of investigation, we cannot avoid the conviction 

 that the results obtained are only a very small part of those 

 in reserve for us in the future. Hence we cannot too forcibly 

 direct the attention of scientific men in all countries to the 

 utility of coordinating their efforts and undertaking methodi- 

 cal investigations in the seas to which they have the most 

 easy access. 



Our zoological groupings now present so many gaps that 

 it is impossible to understand the general. plan which has 

 presided over the grouping of living creatures. Palaionto- 



