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(From the Monthly Micrtncppib^f^Jbuctuil^: August, 1873.) 



REMARKS ON MR. CARRUTHER'S VIEWS OF 

 PROTOTAXITES. 



By J. W. Dawson, I.L D., F.Il.S. 



In tii'! " Monthly Microscopical Journal" lor October, 1872, 

 Mr. Carrutlier.«. ^>t' tlic Biitit*li Muscuju, has published a paper 

 Id which he endeavours to show that my Prototaxites Logani, 

 from the Devonian of Gaspe, is a gigantic seaweed, for which he 

 proposes the generic name Ncm<itophycua. Though I .saw this 

 ^ article some time ago, other avocations have prevented me from 

 attending to it until now. 



The tone and manner of the article, 1 may s.ty in passing, are 

 unnecessarily ofFi'iisive; and the author bolsters up his argument 

 by unfair assumptions that I am ignorant of some of the most 

 familiar facts of structural botany, facts which were well known 

 to me while he was yet a school-boy, and which are stated or im- 

 plied in many of my papers on fossil plants. Possibly, however, 

 Mr. Carruthers is already aware of his bad taste in this matter, 

 and it will be to me a sufficiently ungracious task to expose, as t 

 must do in the interest of truth, the worthlessness of the expla- 

 nation which he offers of the nature of Prototaxites. I shall 

 reply to his objections under the following heads: — (1.) The 

 mode of occurrence of Prototaxites. (2.) Its microscopic struc- 

 ture. (8.) Its probable affinities. 



1. MinJe of Occurrence. — This alone should suffice to convince 



kany practical palaoontologi.st that the plant cannot be a sea-weed. 

 Its large dimensions, one specimen found at Gaspe Buy being 

 three feet in diameter ; its sending forth strong lateral branches, 

 and gnarled roots ; its occurence with land pl<*nt8 in beds where 

 I -- there are no marine organisms, and which must have been de- 

 posited in water too shallow to render possible the existence of 

 the large oceanic Algae to which Mr. Carruthers likens the plant. 

 These a. a all conditions requiring us to suppose that the plant 

 grew on the land. Further, the trunks are preserved in sand- 



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