i902] Collins, — The Distinctive Features of Iris Hookeri 179 



or only very slightly known ; and I am convinced that many more 

 are only waiting for me to call again and make their acquaintance. 

 Malden, Massachusetts. 



THE DISTINCTIVE FEATURES OF IRIS HOOKERI. 



J. Franklin Collins. 

 (Plate 39.) 



In the February Rhodora 1 Dr. G. G. Kennedy records the rinding 

 of Iris Hookeri, Penny; at Cutler, Maine. On the second of July, 

 1902, Dr. Kennedy, Messrs. E. F. Williams, M. L. Fernald and the 

 writer found an abundance of the plant at the station mentioned. 

 Upon comparison with /. versicolor, which grew in close proximity, 

 several important differences were noticed, which as emphasizing the 

 distinctness of the species seem worthy of record. 



I. Hookeri has narrower leaves with more prominent nerves, it is 

 more strict and less glaucous than / versicolor, and it grows in situa- 

 tions where the drainage is apparently better — e. g. along the edges 

 of gravelly beaches and at the crests of the ocean cliffs where the 

 plants are often subjected to baths of salt spray. The spathes are 

 usually greener and appear to be inwardly falcate ; really however, 

 they are conduplicate, strongly pointed, and incurved throughout the 

 upper part. At the base the plant is more or less purplish and often 

 there are purple flecks scattered along the lower portions of the 

 leaves. 



In the flower and fruit, however, the most distinctive characteristics 

 are found. In / Hookeri the inner segments of the perianth (or 

 petals) are totally different from the corresponding parts of /. versi- 

 color. This contrast is well brought out in the accompanying plate, in 

 which figures 4, 5, 6, and 7 represent petals of /. Hookeri and figure 

 8 a petal of /. versicolor, — all natural size. The petals in the former 

 are not only very small and comparatively inconspicuous, but have 

 their edges involute below or even rolled up so as to form a hollow tube- 



1 Rhodora, iv. 23 (1902). 



