382 



Note on the Generic Position of Certain Australian 

 Cam brain Triiobites. 



At tho evening meeting of the Society on October 9 of 

 last year (see vol. xliii., p. 373) a paper was read from our 

 late Honorary Fellow (Robert Etheridge) on the Cambrian 

 Triiobites of Australia and Tasmania. Most of the specimens 

 therein described consisted merely of more or less imperfect 

 cephalic shields, and consequently obscure and difficult of 

 determination. As the author of the paper died before its 

 publication, I took the initiative of sending reprints of the 

 paper to a few American palaeontologists whom I knew to be 

 interested in the subject. One such paper was forwarded to 

 Dr. Charles D. Walcott, who has an intimate and cos- 

 mopolitan knowledge of the Cambrian fauna, and whose 

 judgment on all questions relating to Cambrian palaeontology 

 carries much weight. ' Dr. Walcott has been good enough to 

 express his opinion on Mr. Etheridge' s determination, based 

 upon the very excellent figures of the respective forms 

 described in the paper referred to, and from the interest 

 which Australian geologists take in this subject I think it 

 desirable that Dr. Walcott's conclusions should be made 

 public. 



Under date of March 12, 1920, Dr. Walcott writes: — 

 "I thank you for your letter of February 8, also the paper 

 on the Cambrian Triiobites by II . Etheridge, jun. 

 With relation to Etheridge' s determinations, I do not think 

 that any of the forms on plate xxxix. should be referred to 

 the genus Ptychoparia, but at present I am not prepared to 

 say where they should go, unless it is fig. 1, which may be a 

 Redlichia. Fig. 8, pi. xl., is a good Ptycho'paria^ but fig. 7 

 is not." 



It is only just to Mr. Etheridge to say that he was by no 

 means confident in his determinations, as will appear from 

 the following extract from his letter of transmission, dated 

 September 8, 1919: — "I now after several previous attempts 

 forward you, under separate cover, my MS. on the Cambrian 

 Triiobites for what it may be worth, but, frankly, I am. not 

 satisfied with the production; it is so difficult to handle these 

 small fragmentary organisms. The effusion is for the Royal 

 Society if the Council care to accept it." 



Waltee Howchin. 



Evening Meeting, May 13, 1920. 



