June 13, 1896.] 



SCIENCE. 



87S 



Morris in his Catalogue of British Fossils, 

 perpetuated it. Mr. Seward has examined the 

 specimens and finds them to be in all prob- 

 ability cycadaceous, but he unfortunately de- 

 clines to apply to them either a generic or 

 specific name. This disposes of the last claim 

 of the British Wealden to any monocotyledon- 

 ous vegetation, the old Endogenites erosa hav- 

 ing been long since referred to the ferns. 



The coniferous vegetation of the Wealden is 

 only second in importance to its cycadean vege- 

 tation. It is not as well preserved and there is 

 no doubt much truth in Mr. Seward's remark 

 that "as a general rule, fossil conifers are per- 

 haps the most unsatisfactory plants with which 

 the palEeobotanist has to deal; structureless 

 and imperfectly preserved fragments of broken 

 twigs, isolated cones, leaves or seeds, have 

 usually to be determined separately, and it is 

 only in comparatively rare instances that we 

 are in a position to connect cones and vegeta- 

 tive branches." 



Sixteen distinct forms are enumerated in this 

 catalogue. They are all referred to the genera 

 Araucarites, Pinites, Sphenolepidium, Thuites, 

 Nageiopsis, Pagiophyllum and Brachyphyllum. 

 The largest number of species belongs to Pinites, 

 viz., five, while of Sphenolepidium there are 

 three, and of Araucarites, Pagiophyllum and 

 Brachyphyllum, two each. It is interesting to 

 note that three of the specimens in the Euftbrd 

 collection are referred to Prof Fontaine's 

 Potomac genus, Nageiopsis, and Mr. Seward 

 regards them as probably the same as N. 

 heterophylla Font. Pinites is represented chiefly 

 by cones, which somewhat resemble those of 

 Abies, and this is perhaps the most unsatisfactory 

 group of the conifers. The two widely distri- 

 buted species of Sphenolepidium, S. Kurrianiim 

 and S. Sternbergianum, both originally from the 

 Wealden of Germany, and both of which occur 

 in the Potomac formation, are also found in the 

 Wealden of England. Mr. Seward is disposed 

 to include Prof. Fontaine's S. virginicum and 

 also his Athj'otaxopsis expansa under Spheno- 

 lepidium Kurriammi. Another species is either 

 the same as or closely related to the Sequoia 

 siibulata of Heer, also found in the Potomac 

 formation. It would perhaps not be wholly un- 

 true to regard the genus Sphenolepidium as a 



sort of connecting link between the Araucarian. 

 and the Sequoian types of coniferous vegetation. 



A very brief space is devoted to the coniferous 

 wood of the Wealden, and it would seem from 

 the specimens enumerated that there is in the 

 British Museum no material whatever from the- 

 celebrated ' pine raft ' of Brook Point, on the 

 Isle of Wight. This seems surprising, in view 

 of the great prominence and wide fame of these 

 petrified remains. Only a macroscopic exami- 

 nation seems to have been made of the few 

 specimens from Hastings and Ecclesbourne. 

 This is very disappointing to those who would 

 be glad to avail themselves of the knowledge 

 that could be so easily acquired from this im- 

 portant class of material. If we knew the 

 structure of all the fossil wood of the Wealden 

 of England we should doubtless have a good 

 basis upon which to judge of much of the other 

 material that is so largely in doubt. 



The great botanist, Robert Brown, in the 

 early years of the centurj'^, examined the in- 

 ternal structure of this fossil wood of the Isle 

 of Wight and reported that it agreed with that 

 of the Norfolk Island pine (>4raz«cana excelsa). 

 No figures were ever published that I can. 

 learn. On my brief visit to the island I col-- 

 lected a few specimens, and these have been 

 prepared and slides mounted by Dr. Knowlton. 

 His report upon them is contained in the paper 

 above referred to.* 



The Araucarian type of structure is not found 

 in any of the fossil wood of the Potomac forma- 

 tion, but has been found in that of the Lower 

 Cretaceous of the Black Hills. It is the com- 

 mon type of the Older Mesozoic (Upper Tri- 

 assic) deposits of the Eastern United States. 

 The Potomac wood is all of the Sequoian type, 

 although it has been called Curpressinoxylon. 

 Hitherto no plants of that class have been 

 found in the Wealden, but the occurrence of ' 

 Sequoia suhulata, or a species closely allied to 

 it, together with the forms of Sphenolepidium, 

 seem to mark a transition from the Araucarian 

 to the Sequoian conifers. It may be that the 

 numerous imperfectly ijreserved cones that 

 have been referred to Pinites belong to the ^ 

 same plants whose wood is preserved in the - 



*Sixteenth Ann. Kept. U. S. Geol. Surv., p. 496,, 

 pi. cii., figs. 5, 6 (in press). 



