194 The Microscope. 



Although the cotton plant is familiar to most citizens of the 

 United States, a brief description may be tolerated in this connec- 

 tion. The G. herhacemn is an annual herb of a luxuriant growth 

 on good soil, reaching the height of three to four feet, but usually 

 varying from twenty inches to three feet in height, and spreading 

 to cover about as much in width as its own height. It is no 

 uncommon thing to see a field of cotton where the ground is com- 

 pletely hidden, the plants, set in rows about four feet apart, meet- 

 ing between the rows and interlacing after the field is '' laid by," 

 in a single mass of verdure. The white, pink,'or bluish blossoms 

 are produced terminally on innumerable branches, as many as 500 

 blossoms having been counted on a single plant, and after fertiliza- 

 tion are succeeded by the seed-jiod, or "boll," \h to ?jh inches in 

 length, ovate, and longitudinally ribbed, in which the seeds to the 

 number of from twenty to sixty are produced, surrounded by a 

 mass of fine filamentous cells, constituting the cotton fibre so well 

 known in every quarter of the globe. 



The seeds of the Sea Island cotton are black, elongated and 

 almost free, the cotton adhering pappus-like to one end only. The 

 seeds of the tree cotton are chocolate brown, pyriform, and 

 entirely free from the fibre, which is shorter than that of the Sea 

 Island, although the boll is much larger and longer. The seeds of 

 the upland cotton are dark olive green, often nearly black, oval 

 and densely clothed with the fibre, which, when the contents of the 

 boll are removed in picking, almost c?)nceals the seeds. In this 

 condition it is known as '' seed cotton," the seeds constituting about 

 three-quarters of the total weight of the mass. By passing the 

 seed cotton through a cotton gin the fibre, technically known as 

 "lint," is in great part removed l)y the saws of the gin, leaving the 

 seed, however, still covered all over with a short, downy remnant 

 of the fibre or lint. It is in this condition that the cotton seed is 

 sent to market by the planter, and the examination of the seed will 

 therefore commence at this point, and will be limited to the upland 

 cotton, G. herbacenm. 



Plump, well ripened seeds average about seven to ten Mm. in 

 length by about four to six Mm. in breadth, oval and covered with 

 a matted lint about four to twelve inches long on well-ginned seed. 



Figure 1, Seed. Figure 2, Lint. 



The seed coat or "hull" is a dense, woody fibrous covering, 

 about .3 Mm. thick, tightly investing the kernel, which also is of 

 quite dense consistence. On first examining a radial section of the 



