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discussing the cases which still need adjustment, some of them 

 of considerable consequence in phytographv. 



At the head of the publications upon nomenclature ema- 

 nating from or sanctioned by associations or committees of 

 naturalists which have appeared since the year 1867, De Can- 

 dolle places the Report to the American Association for the 

 Advancement of Science, at the Nashville meeting, 1877, on 

 Nomenclature in Zoology and Botany, prepared by Captain 

 Dall, after much conference with leading American natural- 

 ists. The differences between these rules and those of the 

 botanical code relate mainly to questions mooted by the zoolo- 

 gists, whose systems and views had been comparatively loose 

 and variant. The first alteration in De Candolle's revised 

 draft is adopted from Dall's report, with high commendation, 

 namely : — 



" Art. 3. The essential point in all parts of nomenclature is : 

 1. Fixity in names ; 2. Avoidance or rejection of forms or 

 names which may create error or ambiguity or introduce con- 

 fusion into science." The " fixity in names " is taken from 

 the American code, and is said to supply a real omission. 

 Although merely declaratory, some practical consequences flow 

 from it. The same idea dominates in the report made by 

 Douville, chairman of a committee of the Geological Congress 

 at Bologna in 1881, and which concerned itself with nomen- 

 clature in palaeontology. This report insists that " The law of 

 priority being fundamental in nomenclature, it appears to be 

 necessary to apply it with all possible generality and to sup- 

 press derogations and exceptions to this law. . . . Contradic- 

 tion between the signification of a name and the characters of 

 a genus or species is no sufficient reason for changing such 

 a name," etc. 



Another code referred to is one by a committee of the Zoo- 

 logical Society of France, in 1881, M. Chaper, chairman, in 

 which this principle of fixity is said to be less prominent, 

 more exceptions being allowed. 



On reviewing the whole field, De Candolle assures us that 

 the tendency during the last sixteen years has been : 1, to an 

 increasing agreement of the zoologists with the botanists ; 



