152 NATURAL HISTORY OF MARITIME PINE. 



more resisting power, in proportion as the layers are close and 

 compact. Further, gemmage promotes an active current of turpen- 

 tine from the centre to the circumference, which leaves a considerable 

 quantity of concrete resin behind in the wood tissues which it has 

 traversed. It can thus be understood that gemmage, by retarding the 

 growth, imparts at the same time to the wood qualities which it would 

 only in a state of nature have acquired at a much greater age." 



In regard to semis, or sowings of the maritime pine, it is stated 

 generally that these have to be conducted in every respect as are 

 sowings of the p^7^^^s sylvestris, or Scotch fir; and the following 

 details are given in regard to the pinus maritima : 



" Examination of the Seed. — The seed of this pine is much larger 

 than that of the Scotch fir ; it is grey or brown upon one side, and 

 shining bjack on the other ; otherwise it possesses the same character- 

 istics as the seed of the Scotch fir. 



" Putting in the Seed. — All the various methods of cultivation with 

 which we are acquainted are applicable to the maritime pine. The 

 plough is usually employed for preparing the earth, and the harrow 

 for covering the seed ; the seed being larger requires to be covered 

 with a greater depth of earth. 



" The quantity of seed employed per hectare varies much. In 

 Sologne, for example (as reported by M. A. Brongniart), for a full 

 sowing, about 10 to 20 kilogrammes are used. The difference is 

 owing doubtless to the quality of the seed, or it may be according 

 as the trees are to be close together, or the reverse. We think 

 that from 15 to 1 8 kilogrammes of seed with the wings on, and 12 

 to 14 kilogrammes of seed with the wings off, will be enough, bearing 

 in mind that the seed of the maritime pine is usually of very 

 good quality. For partial sowings these quantities should be 

 diminished by one third. 



" The maritime pine has been cultivated much more extensively 

 lately in several districts in the west and centre of France on account 

 of the peculiar products of this tree. But it is more especially in 

 the Landes and in the La Gironde that it is of chief importance. It 

 is well known that in these departments along the sea-shore from the 

 mouth of the Gironde to that of the Adour, there extends a district 

 called the Dunes of the Gulf of Gascony, which occupies an area of 

 about 240 kilometres in length, by an average breadth of 5 kilometres. 

 The soil of this district, composed exclusively of a very fine quartzose 

 saud deposited on the strand by the waves, becomes so light when 



