ADDENDA TO DESCRIPTIONS OF BURGESS 

 SHALE FOSSILS 



By CHARLES D. WALCOTT 

 (With Explanatory Notes by Charles E. Resser) 

 (With 23 Plates) 

 PREFATORY STATEMENT 



Shortly after his discovery of the remarkable Burgess shale fossils 

 in British Columbia in 1910, Dr. Charles D. Walcott described the 

 more striking species of the major classes of animals and plants 

 represented, to bring to the attention of the scientific world their 

 exceptionally well preserved anatomic details. Subsequent quarrying 

 at the locality yielded many additional specimens of the described 

 forms as well as examples of rarer species not secured in the first 

 season's work. 



During my 1 3 years' association with Doctor Walcott he frequently 

 dwelt upon the fact that he considered his papers on the Burgess 

 shale forms rather in the nature of announcements than as completed 

 studies of these wonderfully preserved fossils. He always intended 

 to return to the study of the described species and to publish more 

 detailed descriptions and interpretations of their form and structure. 

 However, the stress of war times and advancing years prevented a 

 realization of this hope. Nevertheless, from time to time, he had 

 photographs prepared or made notes of his observations regarding 

 structure, all of which were preserved with the collections. 



At the request of the National Museum authorities I have assembled 

 these notes and illustrations for publication so that they may not be 

 lost to science. It must be remembered that none of the statements, 

 and particularly none of the interpretations, in the following pages 

 should be regarded as Doctor Walcott's final opinion, since he recog- 

 nized many of them as tentative. He more than once stated that 

 fully 15 years' work remained to be done on the 35.000 Burgess shale 

 specimens in the National Museum's collections. 



All generic and specific names, having been created by Doctor 

 Walcott, are, of course, to be credited to him, and not to us jointly. 



In order to show clearly exactly what Doctor Walcott wrote and. 

 on the other hand, what I have added — chiefly by way of explana- 

 tion — two type faces are used. Doctor Walcott's manuscript is printed 

 in lO-point type, while the explanations added by me appear in the 



smaller 8-point type. „ t- ^^ 



Charles E. Resser. 



Smithsonian Miscellaneous Collections, Vol. 85, No. 3 



