68 



cordate, on petioles with broad or narrow winged-margins; up- 

 permost lance-ovate to lanceolate ; panicle open and loose; heads 

 of flowers comparatively few, variable in size, but mostly larger 

 than in the type ; rays light blue. 



Common in New Jersey and Pennsylvania, as well as west- 

 ward and southward. 



Aster cordifolius, L., van LAMCEOLATUS, new var. — Leaves 

 deep green On both sides, thin, smooth, faintly scabrous, serra- 

 tures appressed, sometimes nearly obsolete ; cauline ones lance- 

 ovate to narrowly lanceolate, tapering into a long acumination, 

 the cordate sinus almost or quite filled up ; uppermost narrower. 

 In other respects like the preceding. 



Along Chestnut Hill, Easton, Pa., in the deep shade of woods. 

 Also collected on Staten Island by Dr. N. L. Britton and at 

 White Plains, N. Y., by Miss McCabe. 



. Some of the features in these two varieties might suggest hy- 

 bridization with A. ImviSy but the frequent occurrence of the first 

 over so wide an area, and at points where A. IcBvis does not ex- 

 ist, forbids the supposition. 



Thos. C. Porter. 



On Elastic Stamens in Compositse. 



In the Proceedings of the Academy of Natural Sciences of 

 Philadelphia, 1883, I have noted that the filaments of some 

 flowers of the thistle alUance are elastic. The stamens in the united 

 cohimn mature their growth before the pistil becomes fully elon- 

 gated, and which, unable to push through the column, bears it up- 

 on its apex, until the downward pressure is so great that the pis- 

 til bursts through, when the elastic filaments at once draw the 

 anthers down to their proper position on a level with the limb of 

 the corolla. I had supposed that so obvious a behavior in the sta- 

 mens of these plants and those of other Compositae, would be 

 matters of record, — but with the exception ' of what has been 

 written on the irritable filaments (see Sachs' Text-book, pp. jSj- 

 ■jgy) no note seems to have been made. I was pleased to find, 

 on introducing the subject before the combined British and 



* Read before the Botanical Cluh of the A. A. A. S. Cleveland Meeting, i8S8. 



