524 STARCHES OF LILIACE^. 



GENUS TULIPA. 



This large genus comprises over 80 species, a number of recognized botanical varieties, and 

 perhaps materially over 2,000 garden varieties. Originally natives of Siberia, Asia Minor, China, 

 and Japan, they have been naturalized in various European countries, especially those bordering 

 the Mediterranean and Adriatic. They are widely and extensively cultivated in both the Old and 

 New Worlds, notably in Holland, where there existed in 1636-7 a "tulipomania." At this time the 

 tulip-bulb trade had grown to enormous proportions, the bulbs were a common article of specula- 

 tion, and some of the rarer bulbs brought astonishing prices, in one instance as high as 13,000 florins. 

 The garden varieties have had their origin directly or inchrectly from T. gesneriana Linn., which 

 is stated to have been cultivated in Turkey in 1554. The tulips have been classified by Stubenrauch, 

 according to their botanical characters, into 8 groups. The starches of 12 species or varieties, 

 representing 5 of the 8 groups, were examined, as follows: 



Group I. T. hageri Held. 



Group II. T. sylveslris Linn, and T. greigi Regel. 



Group III. T. billietiana Jord. and Fom-., T. didieri Jord., T. didieri var. mauriana, and 

 T. didieri var. fransoniana. 



Group IV. T. clusiana Vent., T. dusiana var. persica Hort., T. ocidus-solis St. Aman., and 

 T. proecox Tenor e. 



Group V. T. australis Link. 



The name T. fransoniana has been used synonymously with T. didieri, and on this account we 

 have included it in the same group as the latter as being identical mth or intimately related to it. T. 

 persica has sometimes been used in commerce as a synonym of T. patens, etc., as above noted, and 

 also to signify Bceometra coluniellaris Salisb. The former is a true tulip; the latter is a monotypic 

 genus, native of South America and not a true tulip. Inasmuch as the starch obtained from our speci- 

 men agreed in its properties with the starches of other tulips, it was concluded that the source was 

 one of the real tulips; and since T. persica has been used synonymously with T. clausiana the speci- 

 men has been so grouped. Tulipa is closely related to Lilium, Fritillaria, Calochortus, and Erylhron- 

 ium, all of which are included in this investigation. The relationship is evident in the fact that these 

 5 genera, including Lloydia and Gagea, have been grouped as constituting the tribe TuUpece. 



STARCH OF TULIPA HAGERI. (Plate 31, figa. 181 and 1S2. Chart 129.) 



Histological Characteristics. In form the grains are simple and are isolated, except a few in the 

 form of doublets. There are no pressure facets. The surface is usually quite regular. In many grains 

 lateral depressions opposite the hilum give the proximal end of grain the appearance of protrusion. 

 Shght lateral projections, chiefly nipple-like, are seen on some of the grains. The conspicuous forms 

 are triangular with rounded angles and curved base, and pyriform in the larger grains; and slightly 

 flattened elliptical, triangular, pyriform, ovoid, and round in the smaller grains. The grains are 

 flattened, and when viewed on edge they are frequently found to be narrower at the distal end. 



The hilum is a distinct, rather small, round, refractive spot with a range of eccentricity from 

 one-fourth to one-sixth, usually one-fifth, of the longitudinal axis. A short fissure, which may be 

 transverse or diagonal, is frequently present at the distal margin of the hilum. 



The lamellcB are usually not demonstrable near the hilum, but occasionally are observed as 

 complete rings, while at the sides and distal end they follow the outline of the grain and are prob- 

 ably incomplete. There are frequently several coarse and refractive lamellae at varying distances 

 from the hilum which are interspersed with groups of fine, less distinct lamellae. The lamellae are 

 more often demonstrable in the area located about one-third to tliree-fourths of the distance between 

 the hilum and distal margin. Rarely they can be counted over the greater part of the grain. An 

 average of 44 has been counted on the larger grains. 



The size of the smallest round grains is 5 by 5yu, and that of the largest grains 54 by 42^1 in length 

 and breadth. The common size of the larger grains is 36 by 30ju in length and breadth. 



Polariscopic Properties. The figure is eccentric, except in some of the very small forms, and 

 is fairly clear-cut. The lines of the figiire are rather broad and generally straight, but tend to be 

 much spread out, especially at the distal margin. Rarely they are either bent or bisected. 



The degree of polarization is fairly high. It ranges from rather high in the large to fair in the 

 small grains. There is some variation in the same aspect antl also in different aspects of a grain. 



