INTRODUCTORT PAPER. 27 



of SO large a district, with their localities, and consequently, each 

 member should record to the Secretary, those which grow in his 

 own neighbourhood. I mentioned above, the age of trees ; they 

 are well worthy of attention and frequently involve much interest, 

 and may be arrived at in the following manner. Trees grow, as 

 you are aware, by the addition, each year, of a new woody 

 layer immediately beneath the bark, which is distinctly marked 

 by the rings which are seen on cutting through the trunk of a 

 tree, and by counting these we may ascertain, with tolerable 

 correctness, the number of years which have passed since it began 

 to grow ; this may be taken as a general rule. I5ut to obtain a 

 correct result, a slip of paper should be placed upon the trans- 

 verse section of the trunk, from the centre to the circumference, 

 on it should be marked with a pencil, the junction of each zone ; 

 upon the back of this slip should be further noted the name of 

 the tree, and the date of its being cut. Hence, in addition to its 

 age, will be obtained a tolerably accurate record of the seasons 

 for the period of its growth, the layers being of various breadths, 

 proving that in some seasons the trees made a much greater ad- 

 vance than in others ; consequently by being particular in noting 

 the date of the cutting of each tree, and commencing \vith the 

 outer layer, it will be found that the layer of any one season in 

 the one tree, will accord with that of the same season in the 

 other. The measurement from the centre gives the radius, this 

 doubled the diameter, and multiplied by six, the circumference. 

 Where transverae sections cannot be obtained, as in the case of 

 growing trees, the circumference should be taken at a fixed dis- 

 tance from the ground, and compared with others of the same 

 species whose age is known. 



If, again, the Island is, as I have mentioned, rich in its 

 Botanical productions, it must of necessity be so also in its 

 Entomological. I am not prepared to give much information to 

 the Entomologist; he must be guided in a great measure by the 

 the soil, and the plants and shrubs which grow upon it. The 

 limestone hills afibrd the marbled white and clouded siilphur 

 Butterflies; and the woodlands have their own varieties, the 

 Lulworth Skipper, &c., as have also, the Tertiary division of 

 the Island ; upon the latter, ought to be found the Emperor Moth, 

 and I have obtained from there several of the rarer species of Beetles. 

 The meadows of Stowborough, plantations of Holme, and the 



