Dr. A. Brauii on the Vegetable Individual. 345 



branches. On the main axis of Cypresses and Thuja there are 

 three- to four-leaved whorls ; on the branches the pairs of leaves 

 are nearly decussate ; this is also the case in Lijsimachia vulgaris. 

 In the same way in Equisetum, the number of the rameal verti- 

 cillate leaves is always inferior to that of the caulinc ones. While 

 thus on the one hand the vegetative branches are nowhere 

 entirely similar to the stem from which they springs on the 

 other hand it appears that those branchlets which seem to bear 

 flowers only are usually more numerous than they seem to be ; 

 since in most cases one, two, or even more small leaves (bractlets) 

 are present beneath the flower, which may easily escape notice 

 on account of their diminutive size, although their existence may 

 be often ascertained with certainty even in those cases in which 

 they are not visible when the flower has reached its complete 

 development*. If we are to deny indi\dduality to those buds 

 (branches) only which are composed of a flower alone, as a strict 



* In fact, all the constant lateral flowers of PrimulacecB, CrucifercE, 

 Capparidece, Resedacea;, BaJsaminecB, Orchidece, never have any bractlets. 

 Among monocotyledonous plants in many cases there is only one bractlet ; 

 among the dicotyledonous there are generally two. Gesncriucece have 

 generally three; Empetrum and Santalum have four, Eriostemon five; 

 Polemoniacece, Cuscutece, and other plants with panicled inflorescence, an 

 indeterminate number. We possess the following means of showing the 

 existence of suppressed bractlets: — 1. The ])osition of the parts of the 

 flower relatively to the axis of origination from which the lateral flowers 

 spring. 2. Analogy. 3. The study of malformations. 4. Obsen-ations 

 of the flower's development. The first criterion can be applied only where 

 we can determine the succession of the paits of the flower. The position 

 of the parts of a lateral flower depends, in fact, upon determinate laws of 

 rameal origination ; when they do not harmonize with these laws, we must 

 conclude that preceding leaves have been suppressed. In this wav, e.g., 

 we can explain the very common position in the 2-5th aiTangement of 

 the calyx Avith the second sepal posterior, by supposing two bractlets 

 according to the fixed law, while it cannot be exjilained without these 

 bractlets. Analog}- aids us most by confirming our conclusions, as e.ff. in 

 the families Scrophularincce, Labiatce, &c., in which many genera present 

 distinct bractlets, while others appear to be without them. In monstrous 

 flowers (in cases of antholysis and chlorysis), sometimes without anv other 

 malformation, bractlets otherwise imperceptible appear in an abnormal 

 growth. Not uiifrequently in Digitalis purpurea, which in its normal 

 state presents no bractlets, but in which we inferred their original existence 

 from aestivation and the position of the calyx relativelv to the axis, I have 

 found bractlets developed in the most heterogeneous degrees, especialh' on 

 the lowest flowers of the raceme of cultivated specimens. C. Schimper 

 and myself have both observed the same fact in Tropceolum majus, which, 

 like most species of this genus, presents no trace of bractlets in the normal 

 state. We have seen them in the form of veiy small, white, subulate 

 leaves, about in the middle of the flower-stalk, wliile the flower remained 

 unchanged in all other respects. Their existence, however, was akeady 

 indicated by the position of the quincuncial calyx relatively to the axis, as 

 well as confirmed by analogy, for Tropcsolum ciliatum, R. et P. (Pojjp. et 

 Endl. Nov. Gen. t. 38), in its normal development has two round and 



