1890.] MICROSCOPICAL JOURNAL. 105 



the second (rain) and fourth ways (saturated soil), the more favorable 

 will be the result. In water-soaked soil cotton will not thrive. It 

 scalds and looks sickly. In the early stages of its growtli the plant re- 

 ceives with advantage a moderate supply of moisture in the form of 

 rain (water in the second condition) , but even then heavy rains are in- 

 jurious^ and later in the season iJicy are absolntely destructive ; the 

 bolls do not open, but fall or rot on the branches ; a surface growth of 

 weeds and grass accumulates so rapidly as to choke the crop ; the boll 

 worm and other insects appear in great numbers, and the crojo is con- 

 siderably cut ort'. Dry years are emphatically those of the largest and 

 best crops." 



In a dry season when the supply of moisture has been moderate, and 

 the plant is young and vigorous, the tap root penetrates to great depth 

 where the supply of soil water is not so much under the control of 

 periodical or ordinary atmospheric changes. The plant is, therefore, en- 

 abled to withstand a long drought; and, if the moisture from the at- 

 mosphere has been given in small quantities all along its growth, the 

 fibre becomes long, even, and soft, the bolls open wide, and the fleecy 

 staple hangs in long, silken folds from them. Much rain and rapid 

 growth of grass in May and June prevent the full development of the 

 tap root, and encourage a great midtiplication of surface roots ; and, as 

 soon as the hot, dry atmosphere of July and August sweep across the 

 fields, the plants wither and shed because there is little tap root to bring 

 up moisture from below the surface of the soil. 



From the examinations it may be concluded that : 



The strongest cotton fibre was produced by Truitt. 



The largest fibre was produced by Barnett. 



The smallest fibre was produced by No. i, Hawkins' Improved, and 

 Peterkin. 



The longest fibre was produced by Okra Leaf. 



The shortest fibre was produced by No. 3. 



The best twisted fibres were produced by Truitt, Rameses, and 

 Cherry's Cluster. 



The largest percentage of fibre per boll was produced by Welborn's 

 Pet, Okra Leaf, Peterkin, Hawkins' Improved, King's Improved, and 

 in the order named. 



The largest percentage of seed per boll was produced by Zellner, 

 Rameses, Southern Hope, Truitt, and in order named. 



The best grade of cotton, taking all things into consideration, is 

 Cherry's Cluster. The second best grade is Truitt. 



The Cuts. — The illustrations representing the longitudinal views of 

 the cotton are given in order to show the tzvist of the fibre ^ and to in- 

 dicate the relative sizes of the difierent strands. The measurements 

 shown in the cuts are photographs made with Zeiss' ocular,micrometer. 

 These photographs were made with Bausch & Lomb's professional 

 photo-micro camera, fitted with Zeiss' objective (0.30 aperture and 16 

 mm. focus) and compensated ocular 6, with micrometer. 



The cross sections shown were magnified with Zeiss' microscope 

 containing objectives 16, and ocular 6. They were drawn by the aid 

 of Zeiss' camera lucida (after Abbe). These sections are given to 

 show what is known to be a well-developed fibre, and one that is im- 

 perfectly formed. The well-developed strand is shown by Okra and 

 Cherry's Cluster, and imperfect fibres are noticed in two figures. 



