COTTON VARIETIES 285 



are so slight that even an expert is unable to identify with 

 certainty any but those varieties having the most definite 

 characteristics. Indeed, the description of any variety 

 will not apply to all the plants in it, but is to be taken 

 rather as a general or average portrayal. 



256. Classification of varieties. The study of varie- 

 ties may be much simplified by arranging them in a small 

 number of groups, as is done in the subjoined scheme of 

 classification. The American upland short-staple cottons 

 may be divided into six classes ; to this is added a seventh 

 division to include short-staple varieties of a character 

 intermediate between any other two groups. An eighth 

 group differs from all the others because its members 

 possess a long staple. 



Group 1. Cluster type. 



Group 2. Semicluster type. 



Group 3. Rio Grande type, of which the Peterkin is 

 an example. 



Group 4. The early varieties of the King type. 



Group 5. The Big-boll type. 



Group 6. The Long-limbed type. 



Group 7. Intermediate varieties. 



Group 8. Long-staple Upland varieties. 



The lines of separation between these groups are not 

 distinct ; one group gradually merges into another. 



257. Cluster group. The varieties belonging here are 

 easily distinguished, (1) by the extreme shortness of the 

 fruit limbs in the middle and upper parts of the plant 

 (Fig. 133), and (2) by the tendency of the bolls to grow in 

 clusters of two or three (Fig. 134). The few base limbs 

 are usually long. The plant in general possesses an ap- 



