LINNEAN SOCIETY OF LONDON. 7 



Observations during several successive years on a large area of 

 Myrica in the peat moors of Somerset show that there is always a 

 small proportion of monoecious plants, which present all gradations 

 between the normal pistillate and ?taminate types, further, it 

 has been found that the sex of a plant may vary from year to 

 year. 



The monoecious plants may be grouped as follows : — • 



(rt) Plants bearing both staminate and pistillate catkins of the 

 normal type. These occur on different shoots, or they may be 

 mixed on the same shoot. In the latter case, usually the lower 

 part of the shoot is staminate and the upper part pistillate, but 

 the reverse order may obtain. Staminate, pistillate, and mixed 

 shoots may occur on the same plant, and the proportions of each 

 vary considerably. 



(6) Plants bearing androgynous catkins. Such catkins usually 

 contain stamens below and pistils above, but the reverse arrange- 

 ment is found also. 



(c) Plants whose catkins consist of hermaphrodite flowers. 

 These flowers (like the unisexual flowers) occur singly in the 

 axils of the catkin scales. Each flower consists of a central 

 ovaiy, surrounded by 3 or 4 stamens (less commonly 2). Just 

 below the insertion of these on the short floral axis, there are two 

 small outgrowths corresponding to the " bracteoles " of normal 

 pistillate flowei's. The pistillate flower consists of an ovary 

 flanked by two " bracteoles " adnate to it, which enlarge and 

 persist in the fruiting stage ; the staminate flower consists of a 

 group of stamens (commonly four), without bracteoles. 



The hermaphrodite flowers are proterogynous. They produce 

 normal fruits, and their stamens are functional. 



Variations of Sex. — Among plants or shoots marked and 

 examined in successive years, some showed progressive change 

 from pistillate to staminate during several seasons ; e. g. plants 

 producing abundant fruit in 1913 showed mixed shoots in 1914, 

 and in 1915 became almost entirely staminate. In 1916 several 

 such cases showed indications of the reverse change. 



Some plants appear to be continually fluctuating, while others 

 remain stable for many seasons. 



Prof. Bateson, Mr. W. C. Worsdell, and Dr. C. E. Moss 

 discussed the paper, and Miss Gibson replied. 



January 18th, 1917. 



Sir Dayii) Pbaiis^ C.M.G., P.E.S., President, in the Chair. 



The Minutes of the General Meeting of the 14th December^ 

 1916, were read and confirmed. 



Mr. Alfred Ernest Knight was admitted a Fellow. 



