H. WORMALD 1S3 



three-lobed and seveii-lobed leaves arc comparatively of rare occurrence 

 under the conditions of growth which obtain in the garden where 

 these observations were made. Only one plant (No. 39) has been noticed 

 on which the leaves are more frequently three-lobed rather than five- 

 lobed; this feature was particidarly noticeable during the past season 

 (1914), and since the individual was planted out in 1909 it is probably 

 a characteristic of this plant, as others of the same age and growing 

 in the immediate neighbourhood produced five-lobed leaves. 



In the Oregon hops, however, the number of lobes varies from 5 to 

 11, the terminal lobe of the English form being often represented by 

 three lobes. The lobing of the leaves of these Oregon plants differs from 

 that of the usual type in other respects. The lobes are more acuminate 

 and the sinuses between the lobes deeper ; as a result of this the lobes 

 themselves are relatively longer. Thus the length of the terminal lobe 

 is about three-c[uarters that of the whole lamina, the length of the lobe 

 being about twice its breadth, and the width at the base {i.e. the distance 

 between the two sinuses) is about half the breadth of the lobe. The 

 corresponding dimensions for an English hop are: length of terminal 

 lobe about two-thirds (usually less) length of lamina; breadth about 

 equal to length; base more than half the width of the lobe. 



Glands on the leaf. On the under surface of the leaves are sessile, 

 capitate, glandular hairs, often just visible to the naked eye but easily 

 seen with a lens. They bear a great resemblance to the lupulin glands 

 found on the bracteoles of the ? inflorescence. The hop owes its 

 bittering property to the resins secreted within the lupulin glands, 

 and it is probable that the glands on the leaves also secrete bittering 

 resins, since it is recorded^ that hop leaves have been used for 

 brewing. 



To determine the variation in the number of glands on leaves 

 of different plants it was found necessary, in order that the results 

 should be comparative, to select portions of the leaves corresponding 

 in position and in area. The method adopted was as follows: a circle 



^ Branngart, in Der Hopfen (Miinchen u. Leipzig, 1901), p. 170, writes: "Merkwiirdig 

 ist, dass man die Laubblatter des Hopfens eben wegen dieser Driiseii in Hopfennotjahren 

 (getrocknet) selion zur Verwendung in der Brauerci, besonders zur Herstellung gcringer 

 • und Naclibiere, empfohlen hat." 



Prof. R. Bradley, of Cambridge University, in The Riches of a Hop-Garden Explained 

 (London, 1729), wrote: "It often happens by haste, that the smaller leaves of tlie plant 

 mingle with the hops. At the time of stripping these leaves are of good virtue, and 

 were alone sold in Flanders, Anno 1566, for twenty-six shillings and eight pence a hundred, 

 no one hop being mingled with them." 



Journ. of Agrio. Sei. vn 13 



