FREAKS OF BULBOUS AND TUBEROUS PLANTS 



to the necessary conditions or surroundings being absent. Occasion- 

 ally, however, we get underground growths like corms being 

 reproduced on the aerial stems. Examples of this have been met 

 with in some Watsonias, where it has been reported that " corms " 

 have been borne in the axils of the leaves. 



In some orchids (e.g. Phalcenopsis Schilleriana and others), young 

 plants develop for some reason on the flower-stems after the blooms 

 have withered. Something similar has been recorded in the case of 

 the genus Marica, in which numerous small plants had developed on 

 the scapes. These plants when detached grew freely, but did not 

 come into blossom so quickly as those raised in the ordinary way. 



It has been recorded by Mr. W. Hales, of Chelsea Physic Garden, 

 that in the case of Achimenes grandiflora numbers of greenish catkin- 

 like tubers were produced in the axils of the leaves. This case is 

 probably on all fours with what happens when these plants are 

 raised from leaf-cuttings. A reference to the drawing at p. 56 will 

 show that these catkin-like tubers develop as a matter of course 

 from the base of the leaves of Achimenes, when they are inserted as 

 cuttings in a suitable compost and temperature. 



The " doubling " of flowers, it is now well known, is due to the 

 suppression or rather modification of the stamens and pistils. These 

 are morphologically only modified leaves, and it is therefore not 

 unnatural that under certain conditions, chiefly when there is no 

 great necessity to develop ripened seeds, some bulbous plants have 

 these organs broadened out into coloured petals. The double 

 Daffodils and Narcissi, double Tulips, double Liliums, double Snow- 

 drops, etc., are well-known examples. Fig. 24 shows a curious 

 development in the flower of Narcissus bicolor Horsfieldi, which 

 appeared a year or two ago in a market nursery at Isleworth. Not 

 only are the usual six segments of the perianth multiplied into 

 several narrow segments, but the number of stamens was also 

 increased. Another plant of N. Horsfieldi bore two almost perfect 

 flowers on one scape, as shown in Fig. 25. 



In the case of the White Arum Lily (Richardia cethiopica) the 

 spathes or floral envelopes, which are usually single, become double, 

 as shown in the accompanying sketch (Fig. 26). The spathe is only a 

 leaf modified for the purpose of protecting the columnar spathe on 

 which the true flowers are seated; and the gradual change from 

 green to white, or yellow, or other colour is easily seen during the 

 period of growth. Fig. 27 shows how even a green leaf is sometimes 

 modified into a pure white spathe. 



37 



