112 



DEVELOPMENT OF 



COLCHICUM AUTUMNALE. 



Fig. 1. Imaginary section of a full- 

 grown plant. 

 a, b. outer dead skins. 



c. dead roots of two-year -old 



corm. 



d. ditto of last year's corm. 



e. roots of present year. 



f. their common sheath. 



g. basal appendage of old corm. 

 h. basal sheath of young plant. 

 i. second sheath. 



k, 1, m. successive leaves. 



n. internodo between first and 

 second leaves. 



o. primary bud. 



p. termination of axis. 



q. peduncles. 



r. remains of two-year-old corm. 



s. ditto of last year's corm. 

 Fig. 2. Young plant, with the en- 

 velopes and old corm 

 removed. 



a. point of attachment with old 

 corm. 



Fig- 



Fig. 4. 



roots. 



their common sheath. 



sheathing leaf. 



second sheath. 



peduncle. 



Young plant still connected 

 with last year's corm, the 

 envelopes having been re- 

 moved. 



scar of old roots. 



basal appendage of old corm. 



old corm. 



dead upper portion of last 

 year's axis. 



second bud. 



Section of old corm and 

 swelling bud. 



basal appendage. 



old corm. 



dead upper portion of axis. 



membrane inclosing young 

 roots. 



o. common axis. 



Iris persica, L. Iris Xiphium, L. 



The flowering bulb, which possesses at its base a small dry 

 stump, the remains of the last year's peduncle, is clothed exter- 

 nally with numerous very thin dry skins. These are followed 

 from their base to the height of from one to one-and-a-half inch 

 by about five scales (Fig. 1 , a), which are already quite dry as far 

 as the upper margin, where they are marked by a scar. Then 

 follow from seven to nine broad fleshy scales, whose tips are yet 

 perfect. 



As regards the height of these, it may be remarked that the 

 lower decrease gradually in length, and this decrease extends from 

 the first to the fourth or fifth ; then they increase again in a 

 higher ratio, so that the uppermost is the largest ; the upper 

 ones, however, are thinner and more membranaceous. Buds 

 occur in the axils of the lower of these leaves whose tips are still 

 perfect (and, indeed, though not so regularly, in the axils of the 

 lower scales), and the size of the buds is in an inverse ratio with 

 that of the mother leaves, the largest bud being found in the axil 

 of the smallest scale (the third, fourth, or fifth). A rather small 

 bud occurs also in the axil of the next somewhat larger scale ; 

 the axils of the three or four upper scales are barren. 



