6 4 



THE BOOK OF NATURE STUDY 



should be examined at different times of year, about November, 

 February, March, July. Drawings should be made of each stage 

 and compared with each other. 



In November the plant is in its resting condition and shows 

 a large corm bearing a bud in the axil of a scale-leaf, with an 

 old corm underneath it. Roots are given off from the circum- 

 ference of the corm. (See Fig. 34.) 



Early in February a crocus has reached the stage shown in 

 Fig. 35. The corm marked I in Fig. 35 is gradually shrinking, for 



the bud (II) is feed- 

 ing on it. If this 

 bud is dissected it 

 will show a succession 

 of sheathing leaves, 

 then a few green 

 leaves, then the floral- 

 leaves all borne by 

 the stem portion of 

 the corm (II). The 

 flowers often come 

 above ground before 

 the leaves ; buds are 

 formed in the axil of 

 one or more leaves at 

 the end of the season, 

 when it is preparing 

 to rest for the winter. 

 After flowering 



the crocus appears as in Fig. 36. The corm has very much 

 increased in size owing to the deposition of starch made by 

 the green leaves, which are always tied up by gardeners after 

 the flower has faded. It is seen in Fig. 36 how very much 

 corm I has shrunk ; if undisturbed, it would very soon have been 

 a mere skin under corm II. This figure also shows the development 

 of a corm from a lateral bud, which was present in the crocus 

 from which it was drawn. The development of new corms from 

 lateral buds is an arrangement by which the plant gradually 

 occupies new ground and thus gets more nourishment. This is 



FIGS. 34-36. Corm of crocus showing three stages of 

 development. The Roman numerals refer to the 

 same corm throughout. 



