724 DR WALTER E. COLLINGE. 



overlooked by later authors, gave an account of the New Zealand species. Stebbing 

 (70) in 1900 described the genus Paridotea with the Oniscus ungulata of Pallas as 

 the type ; and in 1904 (68) the genus Glyptidotea for the /. liclitensteinii of Krauss. 

 NORMAN (47) in the same year catalogued eleven species as occurring in the British 

 Isles. Miss Richardson (55) in 1904 described a new genus, Symmius, for a 

 Japanese species, in which the uropoda each consist of a single piece, the metasome 

 has three segments, the flagellum of the antennae a single joint, and the maxillipede 

 a three-jointed palp. In the same year (56) she described another Japanese genus, 

 Penti as, which is characterised by the five-jointed palp of the maxillipedes and 

 a uniarticulate metasome. In 1905 the same writer (58) redescribed the then known 

 species of North America, amplifying the earlier diagnoses and adding the two new 

 genera Mesidotea and Pentidotea. 



In 1910 Racovitza and Sevastos (52) gave an interesting account of a new fossil 

 species for which they erected the genus Proidotea. 



In 1912 Miss Richardson (60) pointed out that the Cleantis isopus of Miers could 

 not be retained in the genus Zenobiana, and suggested the new genus Cleantiella for 

 its reception. 



Issel (35) in 1913 redescribed and figured Zenobiana prismatica (Risso), 

 pointing out various errors in Bate and Westwood's figures and description, and 

 further showed that Dana's genus Cleantis was synonymous with this. 



Barnard (Ann. Sth. Afr. Mils., vol. x) in 1914 described the new genus Engidotea, 

 a new species of Synidotea (setifer), and three new species of Paridotea, Stebbing. 



In 1915 the writer published a diagnosis of Idotea hectica (Pallas) with 

 figures (14), and also gave a brief account of the species of the family occurring 

 in St Andrews Bay (15). 



III. Classification and Affinities. 



In the various attempts that have been made at a classification of the Isopoda, 

 almost every part of the exoskeleton has at some time or other been employed. 

 Many authors have put forth different systems, but few of them have proved 

 successful or serviceable. 



Of the earlier systems very little need be said, for, as has been frequently pointed 

 out, many of the errors and much of the synonymy arose owing to the imperfect 

 'Icsoriptions and absence of figures, so that an author often confused one species with 

 another ; such conditions are, of course, common to all branches of zoology. 



BRANDT (7) was perhaps the first to realise that certain parts of the exoskeleton 

 were more constant than others, amongst which he specially emphasised the import- 

 ance of the antennae, the telson, and the uropoda. 



Milne-Edwards (45) very largely copied Brandt, but, accepting imperfect 

 descriptions by earlier authors, his work, in this particular respect, has not proved 

 of any great value. 



