THE MARYLAND CYCADS. 409 



received from Sir William Dawson in 1897. I sent him my several papers 

 relating to cycads, and in his letter dated April 19, 1897, he wrote: 



I am glad that you are bringing out the discoveries of my old friend Tyson. 

 When in Baltimore in 1868, now nearly 30 years ago, I went over some of his ground 

 with him, and saw specimens of his cycads and coniferous wood, collecting some 

 of the latter on the clays. He asked me to write about them, but I could not 

 then work at Mesozoic things, being entirely occupied with the Devonian floras. 

 I knew, however, that Carruthers was cataloguing the British cycads in the British 

 Museum, so I sent Tyson some manuscript notes on the coniferous wood, and sent 

 a photograph of one of his cycads to Carruthers, which led to his making the note on 

 it you have referred to. Tyson also gave me a specimen for our College Museum, 

 which is still there, and Carruthers returned the photograph, which I still have. 



In replying to this letter, on May 14th, I said: 



I have seen it stated in one or two places that Tyson referred the cj^cad beds 

 of Maryland to the Wealden. He does not do this in either of his reports as State 

 chemist of Maryland, published in 1860 and 1862. One of the statements I have 

 seen was made by you in your paper ' 'On the Mesozoic Floras of the Rocky Moun- 

 tain Region of Canada" (Trans. Roy. Soc. Canada, Vol. Ill, Sect. 4, 1885, p. 18). 

 Can 3^ou inform me whether Tyson ever said this in print; and if so, where? 



1 did not know that you had one of the Maryland cj^cads. If j^ou could send 

 me a photograph of it I presume I could name it from that. 



Sir William then sent me not onh^ the trunk but also the photograph 

 that he mentions in his letter, which is the same that he had sent to 

 Carruthers, and upon which the latter based the "Postscript" at the 

 end of his memoir. In his letter dated May 19, 1897, he says: 



As to Tyson's cycad, it is a largish trunk, with coarse, large leaf bases, and 

 split down the middle to show the internal arrangements. I shall send you one- 

 half by parcel post or express. . . . The one I have a photograph of seems different 

 from the specimen I am to send. I shall send the photograph also. It is of inter- 

 est, as being the same I sent to Carruthers. 



I fear I can give you no reference as to use of the name Wealden by Tyson. 

 I only remember that in going over the ground he habitually called the formation 

 Wealden, and that caused me to say it was supposed to be Wealden in writing to 

 Carruthers about it and perhaps in mentioning it elsewhere, though I do not recall 

 this now. If, however, I can refer to anything of Tyson's I shall mention it when I 

 send the specimen and photographs. At that time we had very little idea of the 

 successive floras of the Jurassic and Cretaceous, and the reference to the Wealden 

 on grounds of paleobotany could, therefore, be regarded as only general. But 



