96 PROCEEDINGS OF THE AMERICAN ACADEMY 



usage ; but the law of priority is, and would best be, inexorable, and 

 the action of (hose who decry it would relegate our nomenclature to 

 an increasingly chaotic condition. I therefore hold to it as of the 

 utmost importance in nomenclatui'e, as the very foundation of its 

 stability. The changes now required by its strict application are 

 solely due to its neglect in the past. No thought of objection would 

 arise, if it were not so. Entomologists more than others have neglected 

 this law, have frequently acted in defiance of it, and upon them its 

 application falls, as we should expect, most severely. A strict surveil- 

 lance of systematic work hereafter will render the future, it may be 

 hojied, less fruitful in blunders than the past. 



As the work is based upon a chronological order of facts, some 

 remarks are necessary upon two points : the dates of lliibner's 

 different works, and that of Doubleday and Westwood's Genera. The 

 date of lliibner's Sammlung Exotischer Schmetterlinge has generally 

 been given as 180G-o7, the years during which it is supposed to have 

 been issued. But a careful study of the internal and external evidence 

 shows that the dates may be much more closely approximated iu all 

 cases. The first volume contains only and all those plates to which a 

 trinomial nomenclature is appended, and with which, as such, we have 

 here nothing to do. The third volume, or continuation of lliibner's 

 work, must be attributed to Geyer, and dated after lliibner's death in 

 182G. lliibner's Index of 244 plates (including about one hundred 

 and seventy-five species of butterflies), in which he applies a binomial 

 nomenclature to all the species of his first volume, is dated December, 

 1821, and must have been published shortly after the commencement 

 of his second volume ; for he includes in the Index twenty-one species 

 of this volume. Supposing the plates recorded in the Index, and there- 

 fore published from 180G to 1821 inclusive, to have been issued at 

 regular intervals, the first volume must have been completed at about 

 the close of 1819. We may therefore, in default of more precise data, 

 fix upon 1806-19 as the date of the first volume, 1820-21 as that 

 of the plates of the second recorded in the Index, and 1822-26 of 

 those not so recorded. 



This work, however, is not the only one of lliibner's which requires 

 close examination. The Verzeicimiss is dated 1810, and has always 

 been referred to under that date. But internal evidence positively 

 disproves this, and on that account Ochsenheimer's and Dalman's 

 works of 1816 ante-date it. The title-page and preface to lliibner's 

 work, the latter bearing the date 21 Sept., 1816, were printed, as 

 the paging and signature-mark show, at the same time as the first 



