206 CH. WARDELL STILES, 



apparently antedates another although it does not do so actually. 

 In such instances, the ruling of the A, O. U. Code is that the date 

 given 011 the paper shall be assumed to be correct unless it can be 

 proved to be incorrect. If proved to be incorrect, the actual dates 

 are takeii in preference to the dates borne by the publications. 



A case which falls under this general rule has recently occurred 

 in helminthological writiugs. Two papers, one by Looss and the 

 other by Luhe, happen to bear the same date, December 28, 1899. 

 Under ordinary circumstances, these dates would be accepted. It so 

 happens, however, that both authors have proposed new generic 

 names for the same genera, and it therefore becomes necessary to 

 rule that one paper shall be given priority over the other. The 

 natural tendency would be to rule in favor of Looss' paper, since it 

 is a more extensive publication, raore carefully prepared, more clearly 

 vvritten; it contains both the designation of types and füll diagnoses, 

 and in many cases illustrations of the genera. If it were impossible 

 to show that Lühe's paper has any prior claira, it would be natural 

 to prefer Looss' publication. It so happens, however, that froni the 

 evidence at band, the date on each paper is incorrect. In reply to 

 a letter to Professor Spengel, the editor of the Zoologische Jahr- 

 bücher, asking whether a copy of this paper was recorded in the 

 library of the Zoological Institute at Giessen on December 28, and 

 thus open to the public on that date, word has been received 

 that there was a delay of several days in its issuance. If a Single 

 copy could be shown to have been resistered on December 28 in 

 any public library of the world, open to scientific workers, that date 

 could be accepted. The fact that Spengel is editor of the Zoolog. 

 Jahrbücher would not have invalidated the date, in case his Institute 

 were the only one which had it ou that day, for any person could 

 have consulted it in that public institution. Such proof, however, 

 cannot be submitted. A letter has been received froni Dr. Luhe 

 dated March 19, 1900, stating that he has coniniunicated with the 

 publishers of both the Zoologischer Anzeiger and the Zoologische 

 Jahrbücher, relative to the point at band, and that accordiug to 

 their Statements, Lühe's paper was distributed on December 29, 

 Looss' on December 30^). LtJHE further states that Braun accepts 



1) "Sicher ist jedenfalls, dass das Heft der Zoolog. Jahrbücher 

 erst am 30. December zum Versandt gelangt ist , die Nummer des 

 Zoolog. Anzeigers dagegen am 29. December. Diese Angaben rühren 

 von den beiden Verlegern her (Fischer bezw. Engelmann)." 



