33S LAWS OF VARIATION. Chap. XXVI. 



flowers, the nectary aborts ; all the petals become alike both in shape 

 acd colour; the stamens are generally reduced in number and 

 become straight, so that the whole flower resembles that of the 

 allied genus Erodium. The correlation between these changes is 

 well shown when one of the two upper petals alone loses its dark 

 mark, for in this case the nectary does not entirely abort, but is 

 usually much reduced in length. 15 



Morren has described 16 a marvellous flask-shaped flower of the 

 Calceolaria, nearly four inches in length, which was almost completely 

 peloric ; it grew on the summit of the plant, with a normal flower 

 on each side; Prof. TVestwood also has described 17 three similar 

 peloric flowers, which all occupied a central position on the flower- 

 branches. In the Orchideous genus, Phalasnopsis, the terminal 

 flower has been seen to become peloric. 



In a Laburnum-tree I observed that about a fourth part of the 

 racemes produced terminal flowers which had lost their papilionaceous 

 structure. These were produced after almost all the other flowers 

 on the same racemes had withered. The most perfectly pelorised 

 examples had six petals, each marked with black striae like those on 

 the standard-petal. The keel seemed to resist the change more than 

 the other petals. Dutrochet has described 18 an exactly similar case 

 in France, and I believe these are the only two instances of pelorism 

 in the laburnum which have been recorded. Dutrochet remarks 

 that the racemes on this tree do not properly produce a terminal 

 flower, so that (as in the case of the Galeobdolon) their position as 

 well as structure are both anomalies, which no doubt are in some 

 manner related. Dr. blasters has briefly described another leguminous 

 plant, 19 namely, a species of clover, in which the uppermost and central 

 flowers were regular or had lost their papilionaceous structure. 

 In some of these plants the flower-heads were also proliferous. 



Lastly, Linaria produces two kinds of peloric flowers, one having 

 simple petals, and the other having them all spurred. The two 

 forms, as Naudin remarks*, 20 not rarely occur on the same plant, but 

 in this case the spurred form almost invariably stands on the 

 summit of the spike. 



The tendency in the terminal or central flower to become peloric 

 mere frequently than the other flowers, probably results from " the 

 " bud which stands on the end of a shoot receiving the most sap ; 

 " it grows out into a stronger shoot than those situated lower 



15 It would be worth trial to fer- culture,' Feb. 24, 1863, p. 152. 



tilise with the same pollen the central 17 ' Gardener's Chronicle,' 1866, p. 



and lateral flowers of the pelargo- 612. For the Phalaenopsis, see ibid., 



nium, or of other highly cultivated 1667. p. 211. 



plants, protecting them of course 18 Memoires . . d* Vegetaux,' 



from insects: then to sow the seed 1837, torn. ii. p. 17". 



separately, and observe whether the 19 ' Journal of Horticulture,' July 



one or the other lot of seedlings '23, 1861, p. 311. 



raried the most. 20 'Xouvelles Archives du Museum, 



M Quoted in 'Journal of Horti- torn. i. p. 137. 



