] 22 Dr. P. L. Sclater on the Species of the Genus Tribonyx. 



of wliich species Mr. Seeley says it is only a variety. Pholas 

 Dallasii (mihi) appears to me to be nearly allied to D'Orbigny's 

 P. Cornueliana ; and both will, of course, take their place in the 

 subgenus Pholadidea, as indicated by Mr. Seeley. 



Finally, Mr. Seeley says : " The age of the beds is a difficult 

 problem, and not one that can be solved by an appeal to fossils, 

 or mineral character, or superposition." Unfortunately, Mr. 

 Seeley does not inform us how the problem is to be solved, 

 unless he wishes us to receive his hypotheses without requiring 

 any proof. If I am honoured by a reply to my remarks, I may 

 remind Mr. Seeley that, although the opinion of an eminent 

 geologist must have great weight, yet it is by no means weakened 

 by an appeal to facts, and that it is hardly fair to adduce in 

 support of his arguments results said to be detailed in a book 

 still unpublished, or in papers which have not yet appeared in 

 print*. 



XVIII. — Note on the Species of the Genus Tribonyx. By P. L. 

 ScLATEB, M.A., Ph.D., F.R.S., Secretary to the Zoological 

 Society of London. 



In endeavouring to ascertain the correct scientific name of a 

 fine specimen of a Ralloid bird of the genus Tribonyx, from 

 Western Australia, which has lately been added to the Society's 

 Collection, I have discovered that there seems to have been some 

 little confusion between two of the species of this genus, which 

 I take the opportunity of setting right. 



Upon turning to Mr. Gould's ' Birds of Australia,' to which one 

 naturally refers for the determination of an Australian bird, it 

 is at once apparent that the Society's specimen is not the bird 

 figured there as Tribonyx Mortieri, being distinguishable by its 

 larger size and the distinct white stripes on the wings, although 

 otherwise much resembling it. But, in his original description 

 of Tribonyx Mortieri, Du Bus most clearly describes these 



* Several examples of this citation of unpublished materials occur in 

 Mr. Seeley's paper. I may refer more particularly to that which, as he 

 says, was read on May 27th, 1867, before the Cambridge Philosophical 

 Society, on a deposit near Upware. I was present on that occasion, and 

 heard Mr. Seeley's remarks, with many of which, however, I could not 

 concur, as I stated at the time. Mr. Seeley's so-called paper consisted 

 apparently of an extempore exposition of his views. No list of fossils was 

 given by him ; and the whole paper was quite unworthy of an attempt to 

 revolutionize the geological classification of the Upper Jurassic and Lower 

 Cretaceous beds, in support of which it is cited in the last Number of the 

 'Annals.' I had already communicated (May 7th, 1867) a short paper on 

 the Upware deposit to the Yorkshire Philosophical Society : this is printed 

 in the ' Geological Magazine ' for July. 



