[142] 'Notulæ,' vol. i, Dicot. p. 127. 'Atlas,' pl. xliii.
[143] Moquin-Tandon gives the following references to cases of proliferous roses, but some I have not been able to verify. 'Journ. des Sav.,' 22 Mai 1679. Hottinger, 'Ephem. Nat. Cur.,' dec. 3 ann. 9 et 10, p. 249. Marchant, 'Mem. Acad. Scienc. Paris.' 1707, p. 488. Preussius, 'Ephem. Nat. Cur.,' cent. 7 et 8. App. p. 83. Schuster, 'Act. Acad. Nat. Cur.,' vol. vi, p. 185. Spadoni, 'Mem. Soc. Ital.,' t. v, p. 488. See also at the end of this section for numerous other references.
[144] 'Bull. Acad. Belg.,' t. xx, part ii, p. 271. See also Bellynck, 'Bull. Soc. Bot. Belg.,' t. vi, ex. 'Bull. Soc. Bot. France,' t. xiv, 1867, Rev. Bibl., p. 241. Orchis ustulata.
[145] I have not been able to meet with this, but it is said to contain a paper on prolification, with numerous bibliographical references.
[146] 'El. Ter. Veg.,' p. 364, Adnot.
CHAPTER III.
HETEROTAXY.
Under this category are here included a variety of deviations from the ordinary arrangement and position of parts which cannot conveniently be classed under the preceding or under other headings. The term heterotaxy is intended to apply to the production of organs in situations where, under usual circumstances, they would not be formed. It thus does not include cases of substitution, where one part is replaced by another, or more or less metamorphosed, nor cases of multiplication, nor of prolification which are characterised not only by the production of members in unwonted situations, but also in unwonted numbers. From the very nature of the anomalies, and specially from the scanty knowledge we possess concerning their mode of development, it is not possible to allocate them in all cases correctly, and moreover many of them might as well be placed in one group as in another.
Formation of adventitious roots.—This is of exceedingly common occurrence in a vast number of plants, so much so that in most cases it cannot be considered as in any way abnormal; there are, however, a few instances where the formation of these organs may be considered to come within the scope of teratology, or, at least, where their production is the result of injury or of some unfavorable condition to which the plant is exposed.
Thus the production of adventitious roots on the stem of the vine is considered to be due to untoward circumstances impairing the proper action of the ordinary subterranean roots. So, too, the formation of roots on the upper portions of stems that are more or less decayed below, as in old willows, is to be considered as an attempt to obtain fresh supplies through a more vigorous and healthy channel.
A similar occurrence often arises as a consequence of some injury. Virgil had this circumstance in view when he wrote