2^0 Winton — Anatomy of the Fruit of Oocos nucifera. 



or.). This brown substance is quickly changed to a reddish 

 color by caustic potash, but is not affected by alcohol, ether or 

 the specific reagents for proteids, fats and resins. No imme- 

 diate effect is produced by ferric chloride solution, but on long 

 standing the color is changed to olive green. 



(d) Fibers (Coir). — These are fibro-vascular bundles with a 

 strongly developed sheath of bast-fibers. Toward the xylern 

 side of the bundle, particularly in the large fibers, the sheath 

 usually diminishes in thickness and the vascular portion, as 

 seen in cross section, is more or less eccentric, surrounded by a 

 crescent-shaped sheath with the horns connected by a narrower 

 strip. 



In the smaller fibers there is but one group of phloem ele- 

 ments, but in the larger flattened fibers there are usually two r 

 or occasionally more, groups separated from each other by a 

 continuation of the sheath (fig. 5). Normally the xylem is 

 near the inner flat side and the two phloem groups are approxi- 

 mately symmetrical with reference to the shorter axis of the 

 elliptical cross section ; but often the xylem is near one of the 

 narrow sides and the phloem groups are symmetrical with ref- 

 erence to the longer axis, and still more often the arrangement 

 is diagonal or otherwise irregular. 



Mohl* in 1831 noted that the phloem in the stem of Cala- 

 mus was normally divided into two distinct groups, and Knyf 

 as well as other authors have since found the same arrangement 

 in a number of palms. By the study of many sections, the 

 writer has demonstrated that a cocoanut fiber with two phloem 

 groups has also a double xylem, although in most sections no 

 separation is evident, and the whole fiber consists of two sim- 

 ple bundles united side by side, which may completely sepa- 

 rate further on in their course by the forking of the fiber. 



Serial sections cut through such compound fibers show that 

 at the place of forking the phloem groups are still further sep- 

 arated and the xylem also is divided by bast-fibers, thus form- 

 ing two distinct bundles which pass into the two branches. 

 The phloem in each branch is at first entire, but further on, if 

 the branch is large it usually divides, and still further on the 

 whole bundle niay split up, with the formation again of two 

 fibers. Occasionally a fiber which has no evident division of 

 the xylem has four groups indicating that the fiber is com- 

 posed of four united bundles, which, on branching, form two 

 fibers each with a double bundle. 



Large fibers not only fork but also send off small lateral 

 branches. The rudimentary bundles belonging to such 



* De Palmarum Structura, Translation in Raj. Soc. Reports and Papers, 1849r 

 p. 29. 



f Verhandl. d. Bot. Ver. Prov. Brandenburg, Bd. xxiii, 1881, pp. 94-109. 



