GYMNOSPERMtE. 



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the London Clay, they are generally macerated and abraded. They appear, without 

 exception, to be unripe, or have not shed their seed, and may have travelled long 

 distances before becoming finally waterlogged and embedded. It is therefore open to 

 question whether the Pines from which they were derived were actually indigenous 

 to our Eocene plains or low-lying grounds during the sub-tropical periods, or whether 

 they might not, from the great length of time they would float, have been brought from 

 more hilly countries by river, or even from other lands by marine currents. 



The genus Cedrus comprises four species, or perhaps varieties, which inhabit 

 respectively the Himalayas, the Lebanon, Atlas, and Cyprus mountains. The cones are 

 globose and erect on the upper side of the branches. The scales are thin, leathery, and 

 closely pressed together, and persist for some time after shedding the seed. The cones 

 break up and the scales fall separately, except those of the apex, which are soldered 

 together in form of a rosette. This habit may account for the complete absence of fossil 

 Cedars in the Tertiaries ; the older forms known from the Neocomian having possibly 

 possessed persistent scales. Sections of Coniferous wood are figured in ' Dixon's Geology 

 of Sussex,' pi. xvi, fig. 5, which were redescribed by Carruthers, ed. ii, p. 164, as 

 Cedroxylon Worthingense. Picea has twelve to twenty-four species, with solitary acicular 

 leaves and cones resembling those of the Cedar. They inhabit temperate regions 

 throughout the northern hemisphere, almost to the confines of vegetation. Two Gault 

 forms from Hainault are doubtfully referred to the genus, while fossil species are met 

 with in Iceland and Greenland, the Wetterau Amber-beds, and a few other Miocene (?) 

 localities. Tsuga resembles Picea, but possesses terminal and pendant cones. The five 

 species inhabit Japan, the Himalayas, and North America, and are said to have been 

 found fossil in the same beds as Picea. I have some doubtful cones from the Iron-ores 

 of Ballypalady described at page 74 as Tsuga Heerii. Pitius Crameri, related to Tsuga, 

 is the most widely spread fossil in the Arctic Cretaceous. The only species of Pseudo- 

 TSUGA inhabits from Mexico to Oregon. The eighteen species of Abies inhabit moun- 

 tainous regions of northern and north-temperate regions. The scales are leathery and 

 loosely imbricated and not persistent, as in Tsuga. Fossil species are known from the 

 Jurassic and Wealden, and from Greenland, Iceland, and the European Miocenes (?). 

 Larix possesses seven to ten species, with linear leaves, sohtary or in bundles, and 

 deciduous in all but one species. The cones are small, with leathery persistent scales, 

 and fall in clusters with the dead branches. The Larch extends over the colder regions 

 of Europe, Asia, and America. Three fossil species are described from the Miocene of 

 Frankfort, and one from Austria. 



Several of the Abietitiea, including the common Spruce, formed part of the British 

 Flora in the Pliocene age, for their remains are met with in the Clays at Bacton, Norfolk. 

 All died out, however, owing to unknown causes, except the Scotch Fir, truly indigenous 

 in the Highlands, and were re-introduced by the agency of man. 



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