THE ASSOCIATION OF CHARACTERS 287 



are still to be dealt with. A short description must be given 

 of some of the new instruments for measurement and com- 

 parison, and the collections of samples and pictures of select- 

 ed plants must be mentioned. In the hst of apparatus the 

 "classificators" may be described in the first place. This 

 name is given to small collections of say 15 to 40 ears arranged 

 according to a definite character. For each quality a special 

 classificator is at hand, so for instance, for the size, the shape 

 and the density of the ears. In order to classify an ear 

 it is shoved along the row, until it falls between two ears 

 of the classificator, one beyond and the other behind it. 

 The intervals between every two succeeding ears of the 

 apparatus being marked by figures, the figure on which 

 the ear falls is the indicator of its degree of the character in 

 question. 



The transparency of the grains of barley is measured 

 by means of screens with holes. These are exactly filled 

 by one grain each, and the standard-kernels are arranged 

 according to the degree of their diaphaneity. The grains 

 to be tested are put into similar holes of a Httle separate 

 screen, which can be shoved along the classificator until 

 their transparency coincides with that of one of the standard 

 types. The degree of mealiness is tested by a small pincer 

 which measures the pressure required to squeeze the ker- 

 nels into pieces. Other instruments are so constructed that 

 they collect from an ear or a panicle all the lowest grains, 

 all those of the second rank and so on, in order to determine 

 the average weight of each group separately. As we have 

 seen, the seat of the heaviest kernels is one of the important 

 marks in the testing of varieties of cereals. Many other 

 instruments have been devised in order to make the esti- 

 mates as independent of personal impressions as possible, 

 and thus to make them thoroughly reliable even if they 

 have been made in different years or in different localities. 



