TUE BRIAN OR DEVONIAN FORESTS. 



89 



Shnmar(Vs Filicites gracilis, from the Lavonian of Ohio, and 

 Stur's Pinites antecedens, from the Lower Carboniferous of Silesia, 

 may possibly belong to the same genus. The Scottish specimen re- 

 ferred to is apparently the first nppcarance of this form in the 

 Devonian of p]urope. 



I have at a still later date had opportunities of studying con- 

 siderable series of these plants collected by Prof. Williams, of Cornell 

 University, and prepared a note in reference to them for the Ameri- 

 can Association, of which, however, only an abstract has been pub- 

 lished. I have also been favoured by Prof. Losquereux and Mr. 

 Lacoe, of Pitt3ton, with the opportunity of- studying the specimens 

 referred to Trochophi/llum. 



Prof. Williams's specimens occur in a dark shale associated with 

 remains of land-plants of the genera Psilophyton, Rhodea, &c.. and 

 also marine shells, of which a small species of RhynchoneUa is often 

 attached to the stems of the Ptilophylon. Thus these organisms 

 have evidently been deposited in marine beds, but in association 

 witii land-plants. 



The study of the specimens collected by Prof. Williams develops 

 the following facts: (1) Tlie plants are not continuous fronds, but 

 slender stems or petioles, with narrow, linear leaflets attached in a 

 pinnate manner. (2) The pinnules are so articulated that they break 

 off, leaving delicate transverse scars, and the lower parts of the stems 

 are often thus denuded of pinna> for the length of one or more 

 inches. (3) Tlie stems curve in such a manner as to indicate a cir- 

 cinate vernation. (4) In a few instances the fronds were observed 

 to divide dichotomously toward the top ; but this is rare. (5) There 

 are no indications of cells in the pinnules; but, on the other hand, 

 there is no appearance of fructification unless the minute granules 

 which roughen some of the stems are of this nature. ((!) The stems 

 seem to have been lax and flexuous, and in some instances they 

 seem to have grown on the petioles of ferns preserved with them in 

 the same beds. (7) The frequency of the attachment of small braehio- 

 pods to the specimens of Ptiloplujton would seem to indicate that 

 the plant stood erect in the water. (8) Some of the specimens show 

 so much carbonaceoiis matter as to indicate that the pinnules were 

 of considerable consistency. All these characters are those rather 

 of an aquatic plant than of an annual organism or of a land-plant. 



The specimens communicated by Prof. Lestiuoreux and Mr. 

 Lacoe are from the Lower Carboniferous, and evidently represent a 

 different specie with similar slender pitted stems, often partially 

 denuded of pinnules below ; but the pinnules are much broader and 



