A REVISION OF THE BRITISH IDOTEID^E. 723 



II. Historical. 



This family of Isopoda lias received considerable attention from carcinologists 

 in all parts of the world. Miers (44) in his well-known "Revision" of 1881 has 

 reviewed the work of most of the earlier authors, and as I shall have occasion to 

 mention some when discussing the classification and affinities, no useful purpose 

 would be served in repeating these here. 



The genus Idotea was constituted by J. C. Fabricius in 1798, the first description 

 appearing at page 302 in his Supplementum Entomologia Systematica. Two years 

 previously he had indicated that he intended describing the genus as new in the 

 Supplement (cf. Index Alphabeticus, 1796, p. 86). In this latter publication he 

 used the " nomen nudum" Idothea, but in 1798 at the head of his description he 

 uses the name Idotea, and I agree with Canon Norman (47) that the latter spelling 

 of the name should be retained. Firstly, as he points out, because this is the spelling 

 which is used, and intentionally used, with the description ; and secondly, because it 

 is the spelling which has been almost universally employed for a hundred years. 



Miss Richardson (57) prefers to use the spelling Idothea, pointing out that that 

 of Idotea is preoccupied by Weber, 1795. 



The earlier references to the family by Linne, Pallas, Pennant, De Geer, 

 Risso, Bosc, Latreille, Desmarest, Brandt, Kroyer, Milne-Edwards, Leach, 

 Rathke, White, and others need not be considered here, beyond the remark that 

 frequently the definitions of these authors were insufficient, and that they were not 

 always clear as to the species they were describing. 



Dana (16) in 1853,. in his great work on the Crustacea of the U.S. Exploring 

 Expedition, described six new species of Idotea, and diagnosed the new genera 

 Epelys, Cleantis, and Erichsonia. 



Bate and Westwood (3) gave a good account of the British species, as then 

 known ; and Harger (32) also gave a very full account of those genera and species 

 found on the eastern coast of the Northern United States. 



Miers' (44) work of 1881 was a great advance upon any previously published, and 

 included a discussion of no less than forty-seven species, included in four genera. 



Chilton (11a) in 1885 described the interesting Idotea f estiva from New Zealand. 



In 1894 (46) Norman drew attention to several distinct varieties of Idotea 

 baltica, which have since been elevated by Sars to specific rank. Dollfus (20) in 

 1894-95 gave a brief account of the species found upon the coast of France. 

 Stkbbing (69) in 1895 proposed the name Zenobiana for the genus Zenobia, Risso; 

 and Sars (64) two years later showed, in connection with the Norwegian species, that 

 what had generally been considered by recent authors as only varieties of one and 

 the same species, were in reality referable to no less than six different species, all 

 easily recognisable in both sexes. Benedict (4) in 1897 published a useful revision 

 of the genus Synidotea. Chilton (ll) in 1899, in a paper which seems to have been 



