GYMNOSPERMvE. 



29 



Tribe II.— THE TAXODIE^. 



The genera are Cri/ptomeria, TaxocVmm, Seqiooia, Athrotaxis, and Cephalotaxus, pos- 

 sessing spiral or distichous fohage, and smooth, woody, or leathery, more or less orna- 

 mented cones, except in the last which bears a drupe. All the genera are alike remark- 

 able for the paucity of their living species, which in no case exceed four, and for the 

 restricted areas which these occupy. It would appear from this, and their ranch wider 

 range in the Tertiaries, that they are survivals from older floras. All are natives of 

 temperate North America, or China and Japan, except the Tasmanian Athrotaxis. 



The Permian TJllinannia is the oldest genus ascribed to the Taxodiese, but its true 

 affinities are still somewhat doubtful. A specimen with cones attached, from Solenhofen, 

 was originally described as Athrotoxis, but was transferred by Schimper to the Jurassic 

 genus, Echinostrohus. Other Jurassic and imperfectly known genera, Brachjphylhmi 

 and Leptostrobus, have been placed in this tribe. Its first definite appearance seems to 

 date from the Middle Cretaceous, cones with at least the outward semblance of Sequoia 

 having been obtained in the Gault and Greensand. Prom the Greenland Komeschichten, 

 besides Sequoia, a genus Inolepis, with imbricated foliage and cones of some forty leathery, 

 dorsally-carinated scales, which are very like the male cones of Sequoia (fig. 13, p. 33), 

 is abundant, and has been, I believe, erroneously placed in the Cupressinese instead of near 

 to Glyptostrohus. Another remarkable form from Pattorfik and the Upper Cretaceous of 

 Europe, especially Portugal, and which should also be placed in this tribe, is Cyparissi- 

 dium, also possessing imbricated foliage, and small ovate cones of eighteen or twenty over- 

 lapping, leathery, and longitudinally-ribbed scales. A single but very characteristic scale of 

 Glyptostrohus from the beds at Pattorfik suffices to carry that genus back to the Cretaceous. 

 The Wealden Sphenolepidium appears somewhat remotely allied to Cryptomeria, and the 

 Cretaceous Geinitzia to Sequoia. The existing genus Cephalotaxus may probably be 

 represented in the Arctic Eocenes by Taxites Olriki. Cryptomeria, which forms a 

 tenth part of the forests clothing the three large islands of Japan, is at present unknown in 

 the Tertiaries. The genera Taxodium, Sequoia, and possibly Athrotaxis, are represented 

 in British Eocenes. 



Genus — Taxodium . 



In this genus the flowers are monoecious, the cones globular and ligneous, and per- 

 sistent after shedding the seed, the scales spirally disposed, imbricated, with an expanded 

 ligneous, mucronated or umbonated apex, and tuberculated or embossed margin. The 

 foliage is deciduous or sub-persistent, distichous, or small and scale-formed. There are 



