February 15, 1900] 



NA TURE 



363 



sideration the subgenera which are not numbered, and 

 which we are afraid to count. Then, the authors have 

 adopted a set of rules which, when applied to ichthy- 

 ology, make the greatest possible disturbance in pre- 

 viously accepted nomenclature. So-called rules of 

 priority are made retrospective, uniformly and pedanti- 

 cally : reasons which induced elder authors to select 

 certain names for their genera are set aside, and not 

 even Linnaeus himself is allowed to change his own 

 names ; no regard is to be paid to the character and 

 spirit of a work in which the names take their origin ; a 

 name by a Rafinesque or Swainson deserves as much 

 consideration as one given by Cuvier or Riippell. Both 

 these methods result in a nomenclature which is more or 

 less difficult to grasp by a European systematist. 



Fmally, we have to refer to the manner in which the 

 authors have dealt with "synonymy." This seems to us 

 too scanty to satisfy the wants of the student either of 

 systematic ichthology or of the American fauna. The 

 authors announce as the principle by which they have 

 been guided, to give "enough synonyi"oy to connect this 

 work with other descriptive works, and no more" ; and 

 of such works they mention the first descriptions that 

 have been given of supposed new species or genera, the 

 " Hritish Museum Catalogue of Fishes," Jordan and 

 ( Gilbert's " Synopsis," and " other works in which special 

 information is given." No objection could be taken to 

 the adoption of this principle, but we fail to see that the 

 authors have strictly adhered to it. What we expect in 

 a work specially devoted to a fauna, is full reference to 

 €very paper in which our knowledge of the species of 

 that fauna has been advanced in some respect. Con- 

 sidering the vast amount of ichthyological literature 

 scattered through the American periodicals, a more per- 

 fect collection and arrangement of references would 

 liave been of great benefit to the student, though, we 

 idmit, a work of considerable labour. 



We will mention only one case to show that the scanti- 

 ness in their references may even cause inconvenience 

 to the student. The ichthyological parts of the Reports 

 <if the United States Survey Expeditions were prepared 

 by Charles Girard, and published about the middle of 

 the present century ; they form a considerable portion 

 of those quarto volumes, and were very liberally illus- 

 trated. A great number of forms were described in 

 them, and we learned from them at any rate that a large 

 contribution to our knowledge of the American fauna 

 liad been made in the collections of those expeditions. 

 Unfortunately, the treatment of the subject by the 

 naturalist mentioned was not satisfactory, and it seemed 

 most desirable that the typical specimens should be re- 

 examined and the descriptions revised. What position, 

 now, do these reports take in the " Fishes of North 

 and Middle America"? Indeed, the names of the 

 Girardian species appear therein without exception, 

 many as synonymous with other species, a part as valid 

 species, but reference to an examination of the several 

 types is made only in some of the cases. Thus, of 

 eighteen species described by Girard as Alburnops and 

 Motiiana, reference to a type is made only in eight. 

 Further, the authors refer only to preliminary descrip- 

 tions in the Proceediitgs of the Philadelphia Academy, 

 rarely to the enlarged edition in the " Reports," and 

 MO. 1561, VOL. 61] 



almost every mention of the numerous illustrations pre- 

 pared and published at the expense of the United States 

 Government is omitted. Probably, a great number of 

 those types, which were deposited in the Museum of the 

 Smithsonian Institution, are lost by this time, thus 

 depriving the identifications made by Drs. Jordan and 

 Evermann of much of their authoritative value or finality. 

 Possibly, the authors consider those reports, or at least 

 the illustrations, not reliable enough to be safely quoted : 

 an opinion expressed by the writer of this notice some 

 thirty years ago ; but it would have been well if the 

 authors had given some explanation of the matter in 

 their preface or introductory note. 



A work like the one under review, composed at it is 

 of an immense amount of technical details, which only 

 too frequently have to be gathered from imperfect or 

 even misleading sources, cannot fail to lay itself open to 

 criticism on points of minor importance. But it would 

 be most unjust to the authors to allow such real or sup- 

 posed imperfections to detract from the high merits of 

 their work. It was one of the greatest desiderata in 

 Ichthyology. It is a faithful representation of our pre- 

 sent knowledge of American fishes, and will form the 

 basis for all researches in that field for some time to 

 come. For how many years ? Those are, in our ex- 

 perience, the most useful systematic works which most 

 stimulate the activity of new workers, and, as a natural 

 consequence, soonest yield their position to the progress 

 of discovery and the accumulation of new fact. We 

 anticipate that the " Fishes of North and Middle 

 America" will prove to be one of those works, and hope 

 that, when once a new edition will be required, the 

 strength and knowledge of the authors will still be 

 available for this task. Next to the authors, science is 

 greatly indebted to the Secretary of the Smithsonian 

 Institution for having undertaken the publication of such 

 an extensive work, following so soon the appearance of 

 "Oceanic Ichthyology." The publication of these two 

 monumental works in Ichthology stand now to the credit 

 of the Smithsonian Institution. A. G. 



ASTRONOMICAL PHOTOGRAPHY. 

 Die Photographic der Gestirne. Von Dr. J. Scheiner, 

 a.o. Professor der Astrophysik an der Universitat 

 Berlin, und Astronom am Konigl. Astrophysikalischen 

 Observatorium zu Potsdam. Pp. iv 4-382 ; i plate and 

 52 figures, with an atlas of 1 1 plates. (Leipzig : Engel- 

 mann, 1897.) 



DR. SCHEINER'S book has been before the public 

 for some time, and it is to be regretted that we 

 have not had an earlier opportunity of calling attention 

 to its contents and expressing an opinion on its merits. 

 For a book of this character cannot but grow out of 

 date as processes become obsolete, and as improved 

 methods are adapted. Astronomical photography is 

 essentially a progressive science, and when Prof. Scheiner 

 compiled this book, many of the methods employed were 

 admittedly tentative and not accepted beyond dispute. 

 The direction of the further development of photographic 

 practice was not decided, and even the instrumental 

 equipment best adapted to its ends was, and still is, no 

 settled with certainty. This is no proof that such a book 



