PREFACE. 7 



Much of the material described by Wolker is in very poor condition, 

 and it required a very thorough knowledge of the American fauna to 

 identify the species in all c;ises. Walker's method, according to Butler 

 (Journ. Linn. Soc., Zool., Vol. xn, pp. 40U and 432), and personal state 

 ments to me, was rather peculiar. His habit was to pin into a box. in 

 series, as many specimens as it would conveniently hold, and then begin 

 describing. At the end of the day's toil the box would be closed with- 

 out indication of what had been accomplished, aud next morning work 

 would be recommenced from recollection of what had been previously 

 done. None of the specimens were labeled until the descriptions were 

 in type, and then, using a proof sheet, the printed names were cut out 

 and pinned below the series of specimens, not on the insects themselves. 

 Sometimes it happened that there were more names than insects; in 

 such case the label was pinned into the box and, occasionally, the record 

 "type lost," was made. Thus, sometimes two of Walker's names may 

 refer to the same specimen as well as to the same species, and it is not 

 always easy to ascertain when this is so. Judging from the fact that 

 sometimes the descriptions do not in the least fit the specimens labeled, 

 there is reason to believe that no great care in applying the names was 

 exercised. 



Messrs. Grote and Robinson, and afterward Mr. Grote alone, have 

 examined the Walker material and have identified many of the species. 

 In 1887 Dr. Riley looked over the material carefully and secured colored 

 figures of many of the species theretofore unrecognized. These figures 

 and the notes accompanying them, Dr. Eiley has kindly loaned me and 

 they have been of assistance tome in a number of instances. Mr. But- 

 ler has, recently, in rearranging the collection, published the sy- 

 nonymy of some others of the Walker species. Mr. Grote seems never 

 to have spent sufficient time at the work to get more than a few scatter- 

 ing notes, and most of these seem tohjtve been made without material 

 for comparison and from recollection merely. Yet most of them are 

 correct. Mr. Butler's knowledge of our fauna is altogether too slight 

 to make his notes conclusive in the case of obscure species. Critical 

 or synonymical notes should never be made except upon careful study 

 and comparison by a specialist or one fully acquainted with the fauna 

 concerned. Justice to an author requires that his writings be studied 

 before relegating his species to the synonymy, and if neither time nor 

 opportunity for such study exists, it is simply adding confusion to ig- 

 norance to make synonymical notes on superficial comparisons. 



Mr. Henry Edwards has also on one or more occasions examined 

 portions of the Museum collections, but seems never to have made any 

 systematic study. He has informed me in conversation that he had 

 notes on many of the Bombycids which he intended to put into shape 

 for publication: but his untimely death prevented this. 



The new arrangement of the noctuidsin the British Museum is utterly 

 at variance with accepted standards. Mr. Butler's generic associations 



