116 



SCIENCE 



[N. S. Vol. XXXIV. No. 865 



bit of writing would rarely appeal to any 

 large number of children in an equal degree 

 or in the same way; consequently their rela- 

 tion to it would not be of a strictly compara- 

 tive kind in a literary sense. 



The examples given seem to me absolutely 

 valueless for comparison. Number 607 is the 

 production of an idiot. Number 520 is a 

 quotation; no child in its teens could have 

 conceived it. Number 434, if a genuine 

 original, is the only one showing anything but 

 a lesson poorly remembered, it is the only one 

 not quoted or paraphrased from an adult pro- 

 duction which has any literary merit at all. 

 Wm. H. Dall 



Smithsonian Institution, 

 June 19, 1911 



GENOTYPES ARE THE SPECIES UPON WHICH 

 GENERA ABE BASED 



The case presented by Dr. Stiles on page 

 620 of Science for April 21 last, possesses 

 exceptional importance for the student of 

 muscoid flies. Probably in no other super- 

 family of animals have as many misidentifi- 

 cations been made as in the Muscoidea. 

 Species have been repeatedly confused, com- 

 bined, jumbled and wrongly determined ever 

 since the time of Meigen, if not before, until 

 the tangle has now become frightfully intri- 

 cate in character. Especially within the past 

 decade or two have misidentifications of 

 North American forms enormously increased, 

 so that the literature is now overburdened 

 with the resulting error, from which it will 

 be a labor of great magnitude to free it. 



The principle involved in misidentifications 

 or cases of mistaken identity is always the 

 same for all cases, and the problem is capable 

 of only one correct solution. Of two dia- 

 metrically opposed propositions, one must 

 necessarily be right and the other wrong. 

 While I can see the case clearly from both 

 points of view, the wrong premises of the 

 one view stand forth distinctly in my mind, 

 and I can not grant that there exists here 

 any necessity for arbitrary decision. The 

 whole matter rests, of course, upon the 

 adoption of rational and correct premises. 



Properly approaching the question, its solu- 

 tion is simple, and I need only repeat here 

 the axiomatic title at the head of these re- 

 marks. 



The correct and only logical premises are 

 represented in the axiom that every record 



OF A SPECIES OR OTHER TAXONOMIC UNIT IN THE 

 LITERATURE BECOMES AT ONCE A PART OF THE 

 SYNONYMY OF THE SPECIES OB UNIT INTENDED 

 FOE RECORD BY THE RECORDER. It makes nO 



diilerenee under what name the record be 

 made, the entity referred to remains the same, 

 and the synonymy of that entity is thereby 

 enriched by the name used followed by the 

 name of the author making the record to- 

 gether with the date of same. This pre- 

 cludes confusion whether or not misidentifi- 

 eation exists. The genus X-us Jones, 1900,. 

 unmistakably has for its type, under the con- 

 ditions of the problem as stated, the species 

 alhus Jones, 1900. The genotype can be no 

 other than this, which is the particular form 

 so identified by Jones at the time and by him 

 intended as the type of his genus. Jones has 

 misidentified his genotype with Smith's 

 species, hence the name alhus Jones, 1900 

 (non Smith, 1890), becomes a synonym of the- 

 name that shall finally hold for the genotype, 

 that is to say, the particular form indicated 

 by Jones. It is conceivable that Jones might 

 differently identify the same form at differ- 

 ent times, hence the necessity for a synonym 

 to take the date of publication, which should 

 include the month and day if Jones is a 

 voluminous and frequent publisher. 



The fallacy of the opposite premises is 

 very evident. Were we to admit the latter it 

 would be impossible to present a rational 

 synonymy of forms. In the above case, albus 

 Smith, 1890, has no furlher connection with 

 the matter in hand after it has been proved 

 that albus Jones, 1900, is a different form. 

 It should be evident that an author's record 

 of a form must remain always a record of 

 that form in his sense at the time of record. 

 The name he uses is merely a handle by 

 which we can ourselves find and locate that 

 form. If we ever decide that a record of a 

 form is not a record of the form in the sense 



