28o NATURAL SCIENCE. April, 1894. 



(distichous), while the barren spikelets from opposite groups are placed 

 close together along the centre of the flat face of the ear, hiding the 

 axis. This characterises Hovdeum distichiim, L., which includes all the 

 two-rowed forms ; the ears may be white or coloured, and the glumes 

 may be adherent or free from the grain. On the other hand, the two 

 lateral spikelets may be fertile and the central barren, giving a four- 

 rowed variety {H. vulgare, L.). If all three spikelets in each group are 

 perfect, a six-rowed ear results [H. hexastichiim, L.). If we accept the 

 view that these forms, which Linnaeus regarded as distinct species, 

 are really merely varieties of one, we see a reason for the ease with 

 which cross-fertilisation has been carried out between them. Messrs. 

 Garton tried to obtain a variety in which all the spikelets should be 

 perfect, while the size and quality of the seed should equal that of the 

 best cultivated two-ranked forms. By crossing a six-ranked with 

 one of the best two-ranked varieties, known as Golden Melon, they 

 succeeded, after further crossing, in getting composite varieties bearing 

 grains equal in size and quality to those of the Golden Melon, but, 

 being six-ranked, three times more numerous (see Fig. 3). Similarly, 

 by the repeated crossing of the three well-marked forms of oats, a 

 considerable quantity of luxuriant new forms have been obtained. 



As Mr. Carruthers observes, the important services rendered to 

 agriculture by these gentlemen will be more appreciated when they 

 have secured enough seed of the new varieties to permit of their 

 being grown as farm crops. 



For the interesting illustrations which accompany this article we 

 are indebted, through the kindness of Mr. Carruthers, to the Royal 

 Agricultural Society. 



A. B. Rendle. 



