436 Robertson . — The * Droppers' of Tulipa and Erythronium . 
droppers of Tulipa sylvestris are described in more than one place in the 
Gardeners’ Chronicle 1 by correspondents who failed to recognize their 
true nature. Germain de St. Pierre 2 in 1870 and Loret 3 in 1875 refer to 
them as foliar structures, and compare them with the curious bulb-bearing 
leaves of certain species of Allium . 
But by far the most important contribution to the subject antedates 
most of these references by many years. It is that of Thilo Irmisch 4 on 
the morphology of monocotyledonous bulbs and tubers published in 1850. 
This is a very valuable book, giving an accurate and exhaustive account 
of naked eye observations on the development and structure of bulbs. 
Some parts of the rather lengthy preface show that in spite of the mass of 
detail with which Irmisch dealt, he kept his attention fixed on the larger 
issues. He says, for instance, that ‘ Systematic Botany . . . especially 
in the case of the so-called higher plants, will have to rest upon comparative 
morphology, as Systematic Zoology has comparative anatomy for its essen- 
tial basis,’ and he adds ‘ It would rejoice me greatly if my observations 
should be found not useless as material for a scientific systematic treatment 
of (of course) only an extremely small number of plant species.’ Irmisch’s 
descriptions and figures of the immature Tulip-bulb and its dropper are so 
good that they may be felt to render the present paper unnecessary. My 
excuse is that Irmisch’s work seems unfamiliar to many botanists, and that 
in his account of the droppers (which is confined to those of T. sylvestris ) 
he does not figure the seedling or the flowering bulb, and he leaves the 
anatomy out of consideration. In his own words ‘ The morphology of 
fully developed plants like the comparative anatomy of fully developed 
animals will generally lead to sure results without reference to knowledge 
of tissues. Still cases arise in which the knowledge of the anatomical 
structure of a part will be valuable for the determination of its morpho- 
logical significance.’ As a matter of fact my examination of the anatomy 
has simply confirmed Irmisch’s view as to the morphology of the dropper, 
namely, that it is formed partly of an elongation of a portion of the axis 
and partly of an invagination of the sheathing or dorsal surface of the leaf. 
IV. Erythronium ‘Droppers.’ 
Irmisch 5 has given a full illustrated description of the structure and 
development of the bulb of Erythronium Dens-canis in which the seedling 
1 Gardeners’ Chronicle, May and Sept. 1888. 
2 Germain de Saint-Pierre, Nouveau Dictionnaire de Botanique, Paris, 1870. 
3 Loret, Sur les bulbes pedicelles du Tulipa silveslris, Bull, de la Soc. Bot. de France, 
T. xxii, 1875, p. 186. 
4 T. Irmisch, Zur Morphologie der monokotylischen Knollen und Zwiebelgewachse, Berlin, 
1850, p. 57, and Plate V, Figs. 12-22. 
5 Th. Irmisch, Beitrage zur vergleichenden Morphologie der Pflanzen, Abhandl. der Natur- 
forsch. Gesellsch. zu Halle, Bd. VII, Heft iii, 1863, p. 184. 
