GENUS AMARYLLIS. 625 



STARCHES OF AMARYLUDACEjE. 



Class, Monocotyledones. Order, Liliales. Family, Amaryllidaceae. Genera represented: 

 Amaryllis, Hippeastrum, Vallota, Crinum, Zephyranthes, Sprekelia, Haemanthus, 

 Hymenocallis, Leucoium, Galanthus, Alstroemeria, Sternbergia, Narcissus. 



The Amaryllidaceae includes about 70 genera and 650 species. Starches of representatives of 

 13 genera were studied in this research. 



GENUS AMARYLLIS. 



The genus Amaryllis now includes only a single species, A. belladonna Linn., a native of the 

 Cape of Good Hope and popularly known as the belladonna lily. The many other species hereto- 

 fore included in this genus have been assigned to other genera — the Old World species to Bruns- 

 vigia, Crinum, Hippeastrum, Licoris, Nerine, Sternbergia, and Vallota; and the New World species 

 to Zephyranthes and Sprekelia. The starch of a horticultural form known as A. belladonna major 

 was used as the source of starch for this research. 



STAKCH OF AMARYLLIS BELLADONNA MAJOR. (Plate 51, figs. 303 and 304. Chart 207.) 



Histological Characteristics.— Inform the grains are usually simple, and they are isolated, with the 

 exception of a few which occur in compound grains or in aggregates of few components, and rarely in 

 small clumps. A few isolated grains are found with pressure facets. The svu-face is often irregular, 

 generally due to the following causes: to a nipple-like or a rounded protuberance at the proximal end 

 or at the side nearby; to a shifting of the longitudinal axis which results in a slight curving of either 

 the proximal or the distal end; to secondary sets of lamellae deposited at varying angles to the primary 

 set; to the apparent inclosing of the primary set of lamella by a secondary set which may have a more 

 undulating outline; to flattening of points on the surface, and to the saucer- or cup-shaped depression 

 often found at the distal end or side of a large grain into which a small grain frequently fits very closely. 

 The conspicuous forms are the elongated ovoid to oval and elliptical, with the broader distal end 

 often somewhat squared, pyriform, oyster-shell-shaped, and club-shaped, the small club-shaped grains 

 with quite pointed ends; also triangular with curved base and rounded angles, somewhat clam-shell- 

 shaped, ellipsoidal, almost round, and imperfect boot-shaped. The grains are somewhat flattened, 

 and those broadened at the distal end are seen to be narrowed at this end when viewed on edge. The 

 small and medium-sized aggregates occur usually as doublets and triplets with components of about 

 the same size. Large grains with one to four small adherent grains at the distal end or side nearby 

 are sometimes found. Many of the grains show radicular grooves which may be lines of erosion. 



The hilum is either a round or lenticular refractive spot which varies from slightly eccentric 

 to usually about one-fifth or one-sixth of the longitudinal axis. Often a short transverse fissure, 

 and sometimes a small cavity, is found at the hilum, and sometimes two short longitudinal fissures 

 radiate from the sides of the hilum. 



The lamellae are not generally demonstrable throughout the entire grain. They are often less 

 distinct directly around the hilum and also in a narrow border at the distal end. When near the 

 hilum they sometimes appear as complete circles or ellipses, and often in passing from the hilum 

 towards the margin the first demonstrable lamella has the general shape of the margin of the grain. 

 Near the distal end the lamellae always have the form of the margin of the grain and are probably 

 incomplete. There are usually one to three coarse and quite refractive lamellae which are inter- 

 spersed with groups of finer and less distinct layers. One or more secondary sets of lamellae are 

 occasionally observed at varying angles to the first set; and sometimes a group of lamellae of 

 slightly different character incloses the primary set, a coarse, refractive lamella forming a line of 

 demarcation between the two groups. On grains of large size from 52 to 58 lamellae may be counted. 

 Rarely a very large grain is found with 70 lamellae. 



The grains vary in size; the smaller are 5 by S^t; the larger are 68 by 34/i in length and breadth; 

 the common size is 42 by 20m in length and breadth. 



Polariscopic Properties. — The figure is eccentric. Its lines cross each other obliquely and are 

 rather thin and broader at the margin. They are frequently bent and sometimes bisected. Double 

 and multiple figures are found. 



