702 



THE AMERICAN NATURALIST [Vol. XLV 



to parent varieties or the ¥ 1 generation are kept on blue cards 

 and subsequent generations are recorded on buff, salmon and 

 white cards. This provides for four generations which is about 

 as many as are usually desired, but other colors are available if 

 needed for subsequent generations. Four different blanks in 

 each color are provided known as (1) description cards, (2) cul- 

 ture cards, (3) type cards and (4) blanks which are plain ruled 

 cards used for miscellaneous notes. A description card applic- 

 able to beans is shown in Fig. 1. Cards suitable to other plants 

 may, of course, be easily devised. These cards are not often 

 used but are occasionally very convenient. Figure 2 shows a cul- 



rop(^£— ^-yA^6 Cross §«xu« y/f/O Generation Ca^T^O J? / f ' 1 

 ^JtiOp Q If ft in^^n ^ f g ro*,H 



^^^^^ ^^^f^ V P**L<L -<^Z^f 



ture card that is used for any crop under observation and gives 

 all necessary information concerning the care, cultivation and 

 growth of any lot of plants. 



The type card shown in Fig. 3 is the most important and dis- 

 tinctive feature of the system. A single line is given to each 

 plant and furnishes opportunity for recording easily and quickly 

 a wide range of observations. Each hybrid between parent vari- 

 eties is given a serial number that is stamped at the top of the 

 first column and beneath this are entered the numbers of the in- 

 dividual plants. Hybrids between different individuals of a 

 variety are distinguished by the addition of a letter to this num- 



