Botanical Society of Edinburgh. 71 



Chrysanthemum eegetum — N. A., 35 deg. 



Veronica Beccabunga — N. A., 45 deg. 



Polygonum Persicaria — N. A., 40 deg. 



Apargia autumnalis — N. A., about 50 deg. 



Carduus arvensis — N. A., 35 deg. 



Lapsana communis — N. A., about 40 deg. 



Lamium album and L. purpureum — N. A., 45 deg. average. 



Geum urbanum — N. A., 35 deg. average. 



Vicia lutea—^. A., for branches and leaflets, about 45 deg. 



Achillea Millefolium — N. A., for branches and divisions of leaflets, 

 35 deg. 



Veronica Chamcedrys — N. A. varies from 35 deg. to 45 deg. 



Teucrium Scorodonia — N. A., 35 deg. 



Anthriscus sylvestris — N. A., about 45 deg. 



Mentha arvensis — N. A., 40 deg. average. 



Urtica urens — N. A., 49 deg. 



Atriplex patula — N. A., 45 deg. average. 



These angles have been deduced from the measurement of numerous 

 specimens in different localities, and where the word 'average* is added, 

 it is to be understood that the angles of branches and veins of leaves 

 vary equally, and the one stated is taken about the middle of the 

 plant and the middle of the leaf. 



Assuming the foregoing observations to have been accurately made, 

 it would appear that Dr. M'Cosh's views are borne out in a very re- 

 markable manner, and demand still further investigation. We find in 

 plants divisions and subdivisions carried out with surprising regularity, 

 so as often to give the leaf a form resembling that of the whole plant, 

 and we find on measuring these successive divisions that equal angles 

 have generally been maintained throughout. 



In sending the paper. Dr. M'Cosh writes as follows : — 



In July 1 spoke with considerable hesitation of the angular mea- 

 surements. I can now state with great confidence, that there is a 

 most wonderful correspondence between the angle of the venation of 

 the leaf and that of the ramification of the stems. My plan is to take 

 a freely growing branch from a healthy tree, and measure the angle 

 of the branchlets. The careful measurement of a few such branches 

 will give the normal angle of ramification, and it will be found to be 

 much the same as the angle of venation. I have also an idea, that 

 all spines are at a wide angle, and that branches tending to become 

 spines are at a wider angle than the normal one. 



Mr. Mitchell is a schoolmaster at Edzell ; he is possessed of exten- 

 sive scientific knowledge, and is a respectable botanist. 



3. " Tables illustrative of the Morphology of Plants,'* by the Rev. 

 Dr. M'Cosh. 



I. Woody Plants whose leaves have little or no petiole, and which 

 have branches along the axis from near the root. 



Boxwood. Holly Beech. 



Privet. Philadclphus. Oak. 



Bay Laurel. Laurustinus. Elm. 



Portugal Laurel. Arbutus. Alder (very small). 



