62 BRITISH EOCENE FLORA. 



Genus — Pinus, Linn. 



The flowers are monoecious ; the male flowers are produced in dense clusters or 

 spikes at the extremities of the branches, and the female flowers either solitary or in 

 whorls. The cones are ovate, conical, or oblong, generally sessile, persistent for a long 

 while, solitary or in clusters, and varying in size from that of a walnut to a length of 

 nineteen inches or even more. The scales are spirally disposed, numerous, woody or 

 subligneous, generally thickened at the apex, persistent, closely imbricated, and gaping 

 when ripe. The seeds are in pairs, two under each scale, and are more or less oval and 

 pseudo-samaroid, or rarely wingless. The leaves are acicular, sometimes very long, and 

 in sheaves of two, three, or five. The subdivisions, " Binae," " Tematse," and " Quinae," 

 founded on the number of leaves in a fasciculus, and generally adopted as a basis of 

 classification, are rejected by Bentham and Hooker as being based upon an inconstant 

 character. The two natural sections, Pinaster, and Strobus, may be distinguished, the 

 first by the woody nature of its cones, with scales closely pressed together before 

 dehiscence, the heads rendered more or less quadrate by this mutual pressure, and with 

 raised or depressed areola, and central umbo or mucro. The indigenous Scotch Pine, 

 the introduced Maritime Pine, and nearly all the Pines of Europe, belong to this section. 

 The Strobus Pines have cones of loosely-imbricated concave scales, leathery in texture, 

 thickest in the middle and thin at the margins, and with minute or obsolete umbos. 

 The Himalayan P. excelsa, P. Lavibertiana, or the Sugar Pine, P. strobus, and P. cembra, 

 are examples of the group. 



The Pinaster section contains sixty or seventy recent species, and Schimper 

 enumerates a still larger number fossil. The oldest forms are from Solenhofen ; and the 

 Gault of Hainault contains, according to Coemans, connecting links between the two 

 sections. 



Strobus appears to possess not more than thirteen living, and about twenty fossil 

 species, the oldest of which is from the Neocomian of Greenland. 



Pines are confined, like all the Abietineae, to the Northern Hemisphere, but stretch 

 into the neotropical region along the mountains of Mexico. They are quite absent from 

 the Ethiopian and Australian regions, though one species ranges to Java. 



Notwithstanding its exclusion from southern regions it has the widest range of any 

 genus of forest trees, for it extends from the perpetual snows of the Arctic Regions to 

 Mexico, where it mingles on the high grounds with Feather-palms, and to the southernmost 

 points of Europe and Asia. A single species, P. sylvestris, stretches from latitude 70° in 

 North Lapland and 65° 15' in East Siberia to 36° in Persia, thus reaching over at least 

 34° of latitude and 150° of longitude. Frequently two species of Pine mingle to form 



