g 



1 8. Z'. indigotica^ Cooke & Peck. . . , N. K, p. 83 



19. F. ciuurbitaria^ Cooke. . . . N, _/., p. 84 



20. Z'. dispersa^ Gerard. . . . . iV", K., p. 84 



21. Cenangiicm triangulares (Schw.). N. J.^ Mass., p. 114 



22. Phacidium criistaceiim^ B. & C. . . Mass,^ p. 115 



23. Phacidium autumnale^ Fckl. . . . lowa^ p. 131 



24. Patellaria ferriigiiiea^ C. & E. . . iV". J.^ p. 150 



25. Phacidiu?n denfafum^ Schmidt. , , N. K, p. 155 



26. Di see II a discoidea, C. & P. . , iV'. K, p. 170 



27. Phacidium carbo?iaceum^ Fr. . . TV^. K., p- 172 



28. Discella leguminum, Cooke. . . Texas, p. 174 



29. D. macrosper^jia^ Peck N. Y.^ p. 174 



30. Eustegia^ Magnoliae, Peck. . . 6'. Car. p. 175 



31. Patellaria, lignyota, Fr. . , . -A^. /"., p. 175 



New Bedford, Mass. 



H. W. 



Nutation in Epilobium angustifolium, L.— This plant, which 



is put down in the botanies as willow-herb, but is more frequently 

 called fire-weedj exhibits the phenomenon of nutation in a very 

 marked and interesting manner. The young flowers-buds at the tip 

 of the raceme are erect. A little later, as the stem (axis of inflores- 

 cence) elongates, they point downwards and are closely pressed 

 against the stem. Still later, the peduncles of the half-grown flower- 

 buds begin to rise, and soon form nearly a right angle with the stem. 

 Later still, when the buds are fully developed and begin to open, the * 

 angle is lessened to about forty-five degrees ; while the fruits, when 

 mature, are, for the most part, nearly or quite erect. Thus the 

 flowers, or at least the ovaries, from the time of their formation to 

 their fruiting, traverse, twice over, the arc of a circle of nearly ninety 

 degrees. What advantage the plant gains by these movements it 

 might be difficult to say. Possibly the movements may have some 

 relation to those which are known to pertain to the stamens and 

 style. Observations during the growing season, by any one having 

 the opportunity, would no doubt bring out some interesting facts. 

 Cornell University. A. N. Prentiss. 



Growth of Exogens. III. -This subject is one of such import- 

 ance to science that I feel anxious to put before the botanists of the 

 country all the information thai comes into my possession. 



In a conversation with one of the professors of Washburn College, 

 Topeka, Kansas, on the growth of Exogens, he informed me that for 

 some years he had charge of the trees upon the college grounds* 



In order to get shade as soon as possible, the cottonwood {Popu- 

 lus momlifera) had been set alternating with other trees, with the de- 

 sign of removing the cottonwoods as they grew large enough to in- 

 terfere with the growth of the more desirable trees. 



In that locality a dry season occurs with marked constancy, be- 



