June 11, 1909] 



SCIENCE 



935 



from Laeepede, 1799, and tte type from 

 Proriep, 1806. The genus has been current 

 for more than a century, during which period 

 the same species has been repeatedly and inde- 

 pendently designated as its type by various 

 subsequent authors. 



Forster in 1Y88 published a work (" Enchrid. 

 Hist. Nat.") in which he gave diagnoses of the 

 genera of birds (and other animals) then 

 known to him, but without referring to them 

 any species. Some of them were for the first 

 time characterized and named, among them 

 the genus Gavia. His diagnosis, with the 

 context, shows unequivocally that Gavia was 

 proposed for the loons, a group comprising, 

 as now known, some half-dozen species, all 

 strictly congeneric, and so different from all 

 other birds as to constitute a distinct super- 

 family. Gavia was, furthermore, the first gen- 

 eric name proposed for the group. It only 

 remained for some one later to select some one 

 of the loon species as its type. 



Muscivora was proposed by Laeepede in 

 1Y99, for a genus of tyrant flycatchers, but 

 he referred to it no species. It was not satis- 

 factorily determinable till a species was re- 

 ferred to it by G. Fischer in 1813. 



Ouvier in 1800 published ("Leg. d'Anat. 

 comp.," tab. ii.) a considerable number of 

 genera now currently accepted from this 

 source, without giving either diagnoses or 

 other basis for them beyond citing their 

 equivalent vernacular French names, which 

 names are, however, identifiable from a slightly 

 earlier work (" Tabl. elem. de I'Hist. nat.," 

 1Y98) of the same author where these ver- 

 nacular names are coupled with their proper 

 technical designations. In a few cases his 

 generic names are not thus identifiable, and 

 are hence to be ignored. 



These examples, selected from many that 

 are available,' seem to show clearly that " gen- 

 era without species " should be dealt with 



^ For example, Lao^pMe, in his " Tableau . . . 

 des Oiseaux" (1799), recognized 130 genera of 

 birds, of which 19 were here first proposed, all 

 solely on the basis of diagnoses; of these 11, or 

 more than one half, are now, and always have 

 been, in universal use; the others were homonyms 

 or preoccupied names. 



according to their individual merits. They 

 seem also to fully answer Professor Cockerell's 

 question, " Who can define a genus except as 

 including species ? " 



It may be noted further that while this 

 question is not considered in the International 

 Code, it is fully discussed and provided for in 

 the A. O. U. Code, where a diagnosis is recog- 

 nized as a valid basis for a generic name, with 

 the provision, however, that " a name resting 

 solely on an inadequate diagnosis is to be 

 rejected, on the ground that it is indeter- 

 minable and therefore not properly defixied." 

 This ruling is based on general usage for 

 nearly a century, as well as on common sense; 

 to reject it would result in the overthrow of 

 many generic names that have been current 

 in vertebrate zoology for almost a century. 

 It may be added that while the A. O. TJ. Code 

 of Nomenclature and the International Code 

 of Nomenclature are in perfect accord in 

 respect to principles and spirit, the A. O. U. 

 Code is much fuller and more explicit than 

 the International, taking up in detail a large 

 number of questions not included in the latter. 

 This may well be the case, inasmuch as the 

 A. 0. U. Code is a document of some fifty 

 pages while the International Code is com- 

 prised in a dozen pages. 



Postscript. — Since the above was sent to 

 SciENCK, Professor Cockerell has returned to 

 the subject of " Genera without Species,"" 

 giving abstracts of replies received by him 

 from a number of correspondents in response 

 to a suggestion to that effect made in his 

 former communication.' These replies are 

 not only interesting, but possess some impor- 

 tance as showing the opinions on this question 

 of a number of entomologists and botanists. 

 The twelve gentlemen here represented seem 

 to pretty unanimously agree with Professor 

 Cockerell that (to quote from one of them) 

 " generic names published without any men- 

 tion of included species are to be regarded as 

 invalid " ; or, as otherwise stated, " are nomina 

 nuda." This remarkable unanimity seems to 

 me to be due either to limited experience in 

 this diiScult field, or to a lack of knowledge of 



^Science, May 21, 1909, pp. 813, 814. 

 = Science, February 26, 1909, p. 340. 



