three being aborted." Similar abormalities, he finds among the 

 macrospores of this and other species, are explainable on this 

 hypothesis. This is ingenious, and it may easily be sound as well. 



Having in mind the discovery of Mr. Raynal Dodge {Botan- 

 ical Gazette, XX II., 36 et seg.) that the highly sculptured macro- 

 spore envelope is composed largely of silica, and longing for some 

 method of improving the execrable microscopical definition of 

 the microspore, the writer has made experiments that show the 

 latter also to be enclosed in silica. So much having been ascer- 

 tained, a technique leading to clear definition becomes obvious. 

 One simply dusts the microspores upon a cover-glass, heats this 

 on a piece of metal to incipient redness until only a white powder 

 remains, moistens with turpentine, warms gently and mounts in 

 balsam. The spore- skeletons may now be examined with all 

 kinds of illumination, and with the strongest objectives, even with 

 oil-immersion if desired. Papillae are thenceforth papillae, tuber- 

 cles are tubercles, spines are spines. One at last sees that which 

 is present, and ceases from imagining the non-existent. The 

 silicious envelopes retain their shapes and peculiarities, and the 

 large, spherical microspores of /. Dodgei are in the same marked 

 contrast with the small ones as before burning. Both kinds show 

 a slightly wrinkled surface, the wrinkling being more evident 

 around the edges. None of those examined have any papillae. 

 In this respect, as well as in size and shape, the microspores of 

 this comparatively recent species may vary greatly. 



It may be well enough to add that balsam mounts of micro- 

 spores of Isoetes species in general show a faint sculpture over the 

 surface which recalls, in a far-off way, the sculpture of the macro- 

 spores. In the siiica wall of each spore there is also a long fur- 

 row or folded cleft — possibly a provision for the escape of the 

 spermatozoids. 



Media, Pa. 



Does the climbing fern often grow in the open, as in the case 

 of the Tennessee station which Mr. Ferris described in the last 

 number of the Bulletin ? The only known station for the fern 

 in the vicinity of Washington is an almost inaccessible cat-briar 

 tangle bordering a low sphagnous swamp near the famous old 

 duelling grounds at Bladensburg, Maryland. A little investiga- 

 tion and explanation of its habitat and habit might result in a 

 further extension of range. — William R. Maxon, Washing- 

 ton, D. C. 



