18 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



orbital " appearing ou a darker background were in life the light bronze 

 sjiots surrounded by the network of dark blue. 



The name megacephalus was given to the species by Swainson as a 

 substitute only for calamus C. & V., in accordance with the common but 

 very objectionable practice of altering the specific name when it resem- 

 bles or is identical with the generic one. 



Guich^not's description of the species is based upon that of Guv. & 

 Val., with some few corrections and additions. 



The descriptions of Professor Poey of his C. orhiiarius seem to have 



been chiefly based ou this species, but there is evidence of a confusion 



in his notes, some of his remarks applying rather to C. pennatula^ which 



species is the common Fez de Pluma of the Havana markets. Thus his 



description of the canines (those of the upper jaw small, excei)t the 



second, which projects; those of the mandible scarcely larger than the 



cardiform teeth) and the color of the preorbital (blue streaks, forming a 



network) indicate calamus, while the diffuse blue streak across o])ercular 



region behind eye is found in pennatula but not in calamus. 



Note. — It has been a frequeut custom in zoology, dating from the immediate fol- 

 lowers of Linnaeus, to take for a generic name the original specilic name of the typi- 

 cal species, and then, to prevent the tautological use of the same word for both genus 

 and species, to change the specific name, thus establishing a '• new species," as well as 

 a new genus. In such cases at least six different modes of procedure have been advo- 

 cated and more or less consistently followed by different writers. These are the fol- 

 lowing: 



1. To change the generic name so derived from a specific one. This anangement 

 was Once recommended by the British association, but after a time it seems to have 

 been abandoned by common consent. In ichthyology it would necessitate the change 

 of many of the generic names best known, as, for example, a large share of those of 

 Cuvier in the Regne Animal. Again, and still more imjiortaut, this rule is in itself a 

 direct violation of the law of priority, as important in regard to genera as in regard 

 to sijecies. 



2. To adopt the generic name, and to change the specific name to vuh/aris without 

 regard to previous synonyms. This rule was largely followed by Cuvier and Valen- 

 ciennes, but the fact that it has not been generally followed is sufiScieut argument 

 against its use. 



3. To use the name tijpicus in the above case, without regard to previous synouyms. 

 This has had no general acceptance. 



4. To use in the above cases a genitive formed from the name of the describer of the 

 original sjiecies as a specific name. This has been consistently followed by Professor 

 Malm, who has changed the name of the typical species of many genera {Trachurus, 

 Molva, Lota, etc.) to ^'Linnwi," without regard to other names or synonyms. 



5. To choose as a new specific name when the former specific name is used as generic, 

 the specific name next oldest in the synonymy. This rule is the one generally fol- 

 lowed by authors who have endeavored to be consistent in their nomenclature, and it 

 is the one adopted by nearly all recent authors in America. If the original specific name 

 is regarded as having become ineligible, this seems the proper course to follow. One 

 important disadvantage is that in nearly every case it necessitates the revival of some 

 forgotten and often doubtful and, in itself, worthless synonym. For this reason, proba- 

 bly half the species so named have theirproper nomenclature still unsettled. Incase, 

 also, the genus in question is of doubtful validity, the confusion made by this pro- 

 cedure is considerable. Thus if, with most European writers, we adojtt the genus 



