252 NATURAL SCIENCE [October 



' accessory branchiae ' in certain aniphipoda to which the late 

 Professor Wrzesniowski first called attention. In appearance 

 Anaspides not only has seven thoracic segments distinct as in the 

 Amphipoda, but also a segment immediately in front of these 

 distinct. Here, however, Mr Caiman maintains that the appearance 

 is delusive, and that we have only to do with the well-known 

 cervical groove of the carapace. He may be right. He may be 

 wrong. The suggestion is certainly very ingenious. It would be 

 inconvenient here to follow him into the details of so technical a 

 question, or through the important comparison which he institutes 

 between Anaspides and the palaeozoic Crustacea, Pcdacocaris, Gamp- 

 sonyx, and Acanthotdson. To all seeming, however, Acanthotclson is 

 much nearer to the isopod genus Apiscudes than to a schizopod, and 

 the figures of Packard's restoration would have been better omitted,, 

 since they do not agree either with the original figures of the fossils 

 or with the description given in the text. Meek's figures (Geological 

 Survey of Illinois, vol. III., p. 549, etc., 1868) probably give all the 

 information that can be depended upon. 



Professor Gr. 0. Sars (12) is bringing out in rapid succession 

 the parts of his Isopoda of Norway, always with the fulness of 

 satisfying illustration and exact description for which his work is 

 celebrated, throwing a flood of light upon groups, such, for example, 

 as the minute species of Munna, which before were puzzling and 

 obscure. In his account of the Anthuridae he does not notice, and has 

 perhaps forgotten, the view taken by Dohrn and Gerstaecker, and later 

 brought into prominence by Dr Charles Chilton (3), that in this 

 family the longer branch of the tail-feet or uropods is not the inner 

 branch, as authors have generally supposed, but in accordance rather 

 with homology than appearance, the outer branch. Dr Chilton also 

 doubts whether this longer branch is ever really two-jointed, though 

 it is open to maintain that it is sometimes actually and always vir- 

 tually so. These are points on which the Norwegian professor's ex- 

 pressly declared opinion would be of much value. For the correct 

 name of the very common Isopod, generally known as Idotea tricus- 

 pidata Desmarest, Professor Sars selects 'Idothea haltica (Pallas).' As 

 the synonymy of this species was exhaustively investigated by 

 Harger in 1878, by Miers in 1881, and by Dollfus in 1895, it is 

 amusing to note that, in the name finally adopted by each, they all 

 differ from Sars and each one from the other. Harger was unable 

 to consult Pallas' work. He therefore acknowledges that Meinert 

 (1877) may have rightly regarded Oniscus balthicus Pallas as the 

 earliest name of the species. The generic name Idotea came into 

 the world with one letter missing, and this same much victimised 

 letter is found as a superfluity in the specific name hdthicus, so 

 that Idotea balthica (Pallas) will be the form upheld by those of 



