212 TRAGOPOGON PRATENSIS IN THE CENTRAL COTSWOLDS 



(1950). Separation is eventually normal. The absence of subsp. pratensis has not per- 

 mitted any work on the different numbers reported by Clapham (1952) and Ownbey 

 (1950). 



Two fungous parasites have been of widespread occurrence namely Cystopus cubicus 

 (Strauss ex Unger) Lev. and Puccinia hysterium (Strauss) Rqhling., The former causes 

 white blistering on all parts of the plant and w^hen severe has prevented flowering. P. 

 hysterium is easily detected by its orange coloured sori; infection is invariably severe. The 

 attacked plants develop a sickly yellow colour and the capitula are often severely torn 

 so that they become blind. 



From the notes above, it w ill be seen that m the identification of the subspecies the 

 making of field observations during the morning is of critical importance. Some difficulty 

 w^as encountered in the early observations, but this was resolved when variable floret-length 

 within capitula of single plants was seen to result from ovary elongation following 

 fertilisation. It is possible that the ambiguity which might arise from this fact has been 

 responsible for the large number of previous records for subsp. pratensis in Gloucestershire 

 and in the area of survey. No specimens of subsp. pratensis have been found in the 

 present field work and whilst this cannot be complete enough to be absolute it is obvious 

 that subsp. minor is the prevalent type. 



Detailed examination has shown floral morphology of remarkable uniformity and 

 the m_ain characters in the central Cotswold plants may be summarized as follows : 



Suhsp. Florets Bracts Anthers 



minor Bright, sometimes Red or pink Dark purple to 



pale yellow; approx. bordered brown above, 



half length of bracts yellow below 



Achene 



Chromosome 

 No. 



Outer scaly muricate 

 ridges, tuberculate in 

 between 



12 



In conclusion I should like to thank Mr. J. Stevens for his ready aid and Dr. I. G. 

 Thorpe for his interest in the fungi, also to Principal Botflower for facilities. 



REFERENCES 



CLAPHAM, A. R., 1952, m Clapham, A. R., Tutm, T. G. & Warburg. E. F., Flora of the British Isles. 

 Cambridge. 



DARLINGTON. C. D. & LA COLR. L. F., 1947, The Handling of Chromosomes. London. 

 OWNBEY, M., 1950, Natural hybridization and amphiploidy in the genus Tragopogon. Amer. J. Bot., 

 37, 487-499. 



RIDDELSDELL, H. J., HEDLEY, G. W. & PRICE, W. R., 1948, Flora of Gloucestershire. Cheltenham. 

 WINGE, O., 1938. Inheritance of species characters in Tragopogon. A cytogenetic investigation, Compt. 

 Rend. Trav. Lab. Carlsherg, Ser. Phys., 22, 155-193. 



