Proceedings of the Club 487 



forms were shown, including extremely large specimens of Ptcrid- 

 ium aqiiilinum collected by the speaker in southern France. 



Three species may be recognized in North America. The first 

 of these is the common and variable Pteridium aquilinunt, of which 

 the recently described variety pseudocaudatum Clute is more or less 

 common from New Jersey southward. 



The second species is P. caudatwn found in the extreme 

 tropical portion of Florida. The third, which occurs in the West 

 Indies, seems to be identical with a species originally 'described 

 from Brazil, though it has been confused with Pteris csculcnta, a 

 species originally described from the Society Islands. Species from 

 South Africa, India and the Hawaiian Islands were also mentioned. 



Dr. D. T. MacDougal gave an account of " Carpotropic Move- 

 ments of Flowers," taking his illustrations from plants in bloom at 

 the time. The two classes of movements of flowers are the induced 

 or protective and the developmental or automatic. Of the former, 

 the wild carrot furnishes a good example, its umbels being erect 

 during the day and pendent or inverted at night. The segments 

 of the perianth of the tulip also furnish a good illustration of 

 movements induced by changing conditions of temperature. 



Developmental movements, i. e., those due to forces which 

 originate within the plant, are well shown in the inflorescence of 

 Allium Ncapolitanum. The inflorescence here is nodding when in 

 the bud, but the development of the flowers sends a stimulus to the 

 curved portion of the peduncle, causing it to straighten. In addi- 

 tion, the plant is provided against accident by the fact that each 

 pedicel will bend so as to erect the flower if the peduncle is pre- 

 vented from straightening. Under normal conditions the pedicels 

 take positions separating the flowers equally. In Claytoma Vir- 

 ginia, the buds are nodding, the flowers erect. After fertilization, 

 there is another curvature, more abrupt and nearer the base of 

 the pedicel. In Streptocarpus, the flower-stalk is curved and 

 somewhat coiled in the bud, while the open flower is horizontal, 

 bending the stalk at a right angle, and after fertilization, the ma- 

 turing fruit becomes erect. The movements of the fruit, in many 

 cases at least, are for the better dissemination of the seeds, and the 

 movements of the flower are commonly connected with methods 

 of fertilization. Dr. MacDougal referred also to the curious de- 



