SPIRAL TORSION. 325 
Morren spoke of this displacement of the floral organs 
as ‘* speiranthie.’’? 
Morren draws a distinction between spiral-torsion 
or spiralism and the less regular torsion spoken of in 
the preceding section; in the former case not only 
is the axis twisted, but its constituent fibres also. The 
condition in question in some cases seems to be in- 
herited in the seedling plants. 
The following is a list of the plants in which spiral 
torsion of the stem or branches has been most fre- 
quently observed. (See also under Fasciation and 
Contortion.) 
Hesperis matronalis. Mentha viridis. 
Dianthus barbatus. Fraxinus vulgaris ! 
Pyrus Malus. Sambucus nigra. 
torminalis, Zinnia. 
Cercis siliquastrum! Phylica. 
Punica Granatum. Beta. 
Robinia pseudacacia ! Rumex, sp. 
Rubia tinctorum. Ulmus campestris. 
Dipsacus fullonum ! Casuarina rigida. 
pilosus. Abies excelsa ! 
Gmelini. Lilium Martagon! 
Scabiosa arvensis. candidum. 
*Valeriana officinalis! *Asparagus Officinalis ! 
dioica! Sagittaria sagittifolia. 
Galium aparine! Epipactis palustris. 
* Mollugo ! Triticum repens ! 
verum ! Lolium perenne! 
Hippuris vulgaris! Phleum pratense. 
Veronica spicata. Juncus conglomeratus ! 
longifolia. Scirpus lacustris. 
Hyssopus officinalis. Equisetum Telmateia. 
Thymus Serpyllum. limosum. 
Lamium purpureum ! fluviatile. 
Dracocephalum speciosum. arvense ! 
Mentha aquatica. 
Among the more important papers relating to this 
subject may be mentioned : 
Moquin-Tandon, ‘ El. Ter. Veg.,’ p. 181. Kros, ‘De Spira in plantis 
conspicua.’ Morren, ‘ Bull. Acad. Roy. Belg.,’ 1851, tom. xviii, part i, 
p. 27. Milde, ‘Nov. Act. Acad. Leop. Carol. Nat. Cur., 1839. Ibid., 
vol. xxvi, part ii, p. 429, Equisetum. Irmisch, ‘ Flora,’ 1858, t. i, 
Equisetum. Vrolik,‘ Nouv. Mem. Instit. Amsterdam,’ Liliwm. Schlech- 
tendal, ‘Bot. Zeit., xiv, p. 69, et v, p. 66. De Candolle, ‘Organ. 
1 «Bull. Acad. Belg.,’ t. xvii, p. 196, “ Lobelia,” p. 53, ¢. tab. 
