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SOME OBSERVATIONS ON CYC AS REVOLUTA 

 AND C. CIRC1NALIS GROWING IN LAHORE.* 



By Shiv Ram Kashyap, 

 Professor of Botany, Government College, Lahore. 



The observations described in this paper on leaf-clusters and ovules 

 were made on plants of Cycas revoluta and C. circinalis growing in 

 the Government College Botanic Garden and the Lawrence Gardens, 

 Lahore, Some plants were planted in flower pots and were kept 

 constantly under observation. Cycas revoluta is very commonly culti- 

 vated in Lahore gardens but C. circinalis is not so common. The 

 writer has not come across any male plant of Cycas revoluta in Lahore 

 or in its neighbourhood, all the plants being female. It i3 propagated 

 by means of buds which grow on the underground or aerial parts of 

 the stem. These buds when detached and planted grow into new 

 plants which are naturally female. A few years ago the writer obtain- 

 ed some seeds of this species from Japan and these have produced 

 some plants, but the latter have not as yet produced any flowers. 

 Cycas circinalis is represented by many female plants but so far as 

 the writer is aware there is only a single male plant in this locality, 

 growing in a tub in the Lawrence Gardens. The female plants bear 

 buds in fairly large numbers by which the plant is propagated, but the 

 male plant has never produced any bud and therefore it is impossible 

 to increase the number. Only one male cone is produced each year. 

 It is formed during the rains and ripens towards the end of the rainy 

 season, in August. The longest one measured during the last few years 

 was more than eighteen inches, and the thickest, this year 1920, was 

 nearly twelve inches in circumference at the thickest part. 



Leaf-clusters of Cycas revoluta. — One series of observations on 

 Cycas revoluta was meant to find out the interval between the suc- 

 cessive leaf-clusters. Coulter and Chamberlain, in the recent (1917) 

 edition of " Morphology of Gymnosperms " state : — " In Cycas revoluta 

 it is said that a crown is formed every other year, but information in 

 regard to the duration of the crowns, as they occur in the field, is 

 scanty and uncertain." The observations recorded in this paper throw 

 light on both these questions. No information about these matters 

 is given in Chamberlain's recent book " The living Cycads." 



Seedlings grown from seeds showed what is well-known, that the 

 leaves at first appear singly and later on the number is gradually 



increased to two, three and more. 



• A paper read before the Indian Science Congress at Calcutta. February, 

 1921. 



