1911.] 



Herbage Studies. 



475 



face of the sand dunes bordering the St. Andrews Golf Links ; hydrogen 

 cyanide was not detected in this specimen. 



This and last year, it is well known, afford a most remarkable contrast, 

 as in the two seasons the weather has been of very different and 

 opposite types — wet, cold, dull weather having prevailed during the summer 

 of last year (1910), whilst this year (1911) has been characterised by long- 

 continued drought, accompanied by high temperatures and an altogether 

 unusual amount of sunshine. 



Our home experience would lead us to correlate the appearance in Lotus 

 corniculatus of the cyanophoric glucoside and the attendant enzyme with 

 conditions such as have prevailed during the present year — with conditions 

 favouring maturity rather than luxuriance of growth. But apparently some 

 allowance should be made for a factor of variability, which perhaps is 

 Mendelian, on account of differences observed even during the present 

 phenomenal summer in plants growing under conditions which appear to be 

 very similar if not identical. 



In this connection, the following account given of Lotus corniculatus in 

 Bentham and Hooker's ' Handbook of the British Flora ' is of interest : — 



L. corniculatus, Linn., BiroVs-foot Trefoil. — Stock perennial, with a long tap-root. 

 Stems decumbent or ascending, from a few inches to near 2 feet long. Leaflets usually- 

 ovate or obovate ; stipules broader than the others. Peduncles much longer than the 

 leaves. Umbels of from five or six to twice that number of bright yellow flowers ; the 

 standard often red on the outside. Calyx-teeth about the length of the tube. Pod 

 usually about an inch long. Seeds globular, separated by a pithy substance, which 

 nearly fills the pod. 



In meadows and pastures, whether wet or dry, open or shaded, widely spread over 

 Europe, Russian and Central Asia, the East Indian Peninsula and Australia but not 

 reaching the Arctic Circle. Abundant all over Britain. Flowers the whole summer. 

 It is a very variable species, accommodating itself to very different stations and 

 climates ; and some of the races appear so permanent in certain localities as to have been 

 generally admitted as species but in others they run so much into one another as to be 

 absolutely indistinguishable. 



The most distinct British forms are : — 



(a) L. uliginosus, Schk. — Tall, ascending or nearly erect ; glabrous or slightly hairy 

 and luxuriant in all its parts, with six to eight flowers in the umbel. Calyx-teeth 

 usually but not always finer and more spreading than in the smaller forms. In moist 

 meadows, along ditches, under hedges and in rich, bushy places. L. major, Sm. ; 

 L. pilosus, Beeke. 



(b) L. crassifolius, Pers. — Low and spreading, often tufted at the base, glabrous or 

 nearly so, usually with five or six rather large flowers to the umbel. Leaflets broad and 

 often glaucous, especially near the sea, where they become much thicker. In open 

 pastures and on dry, sunny banks. 



(c) L. villosus, Coss. and Germ. — Like the common variety but covered with long, 

 spreading hairs. In dry, sunny situations, common in Southern Europe but in Britain 

 found only in Kent and Devon. 



