128 



BRITISH EOCENE ELORA. 



period, and do not assume any important position until the Oolites are reached. A 

 fragment of foliage with squamiform leaves, imbricated in four rows, appears to have been 

 brought from the Carboniferous of Melville Island, but no other foliage bearing any 

 resemblance to that of a Cupressineous plant has elsewhere been found in rocks inferior 

 to the Upper Trias or Lias. In the older J urassics the branches when met with are small and 

 scattered, but in the Middle and Upper Oolites they are large, numerous, and of many types, 

 though fruits are unfortunately always rare. Along with Widdringtonites, Pala-ocyparis, 

 Thuyites, Phyllostrobus, none differing much externally from living forms, we come across 

 the still existing genus Widdringtonia. 



The Cupressinese are believed by Saporta and Marion to be an offshoot from the same 

 stock as the Taxodiese, with the elements of the cone, diminished in number and more 

 perfectly soldered and combined together, arranged on a decussate or verticillate plan. In 

 the oldest known species of the existing genus, Widdringtonia, the leaves are imperfectly 

 arranged in pairs, and the four scales of which the cones are composed are thought to be 

 metamorphosed from them. The leaves of the Cupressinese, at first irregularly disposed, as 

 shown in J urassic species, finally became in most of the genera regularly arranged in pairs, 

 the lateral being compressed and keeled, and the front and back flattened. The highest 

 degree of complexity is presented by the most recent type, the Junipers, in which the 

 fleshy scales are soldered together so as to convert the cone into an edible berry. There 

 is thus evidence of progressive development in the tribe which is now, next to the 

 Abietinese, the most extensive among Coniferse. 



The Abietine^ are regarded as an ancient tribe, with characters fixed in very remote 

 times, which varied within small limits, and for a long time increased but very slowly in 

 importance. They seem to have descended from an ancestry different from that of the 

 two preceding tribes, whose common origin is apparent in many ways, and which were 

 perhaps originally an offshoot from the stock which produced the Taxese. Saporta has long 

 upheld the view that their cradle was in the extreme north of the hemisphere to which 

 they are practically confined even now. 



The researches of Dr. Nathorst have set the first appearance of the tribe as far back 

 as the Rhaetic of Scania. They reappear in the Inferior Oolite of Spitzbergen, where 

 several genera seem to be present, and have been met with in Norway, Sweden, Siberia, 

 and Spitzbergen, while they are all but unknown in the Jurassics to the south.^ In 

 Cretaceous times, however, they had spread farther south, and in the Neocomian, Gault, 

 and Chalk of Belgium, the north of Erance, Normandy, and England, many curious species 

 occur combining characters which are now distinctive of different genera and subgenera. 

 Thus, the Cembra, Tceda, and Pinaster sections of Pinus were imperfectly separated ; 

 cones like those of Cedar were formed of persistent scales, but were themselves caducous, 

 instead of possessing a persistent axis with scales which fall off as at present ; and the 



1 A small cone •with tbin scales, from the Kimmeridge Clay, is described as Pinites depressus by Car- 

 ruthers, ' Geol. Mag.,' vol. vi, p. 2. 



