MISCELLAXY 



76f 



Dry Thunder-Storms. A correspondent 



in Oregon, Missouri, communicates some 

 observations on weather phenomena, es- 

 peeially upon the influence of forests on 

 rainfall. " When the earth has become dry, 

 parched, and very warm, on occasion of 

 thunder-storms, I have often," he writes, 

 "noticed for hours, while it was thundering 

 overhead, the mist, falling from the storm- 

 clouds, to roll back, after nearly reaching 

 the earth, in the form of lighter vapor. I 

 think this rain, or mist, in falling, passed 

 down to the stratum of very hot air on the 

 earth's surface, and became a steam, large 

 volumes of white vapor forming suddenly 

 and rolling back and up. Now I am con- 

 fident that, if the earth had been shaded by 

 trees, this rain would have fallen on the 

 ground. 



" This phenomenon can be seen here 

 every hot, dry season. It has, no doubt, 

 escaped the attention of all but very close 

 observers. Mine was called to it by a ques- 

 tion asked while one of these dry thunder- 

 storms was prevailing a common thing 

 dry thunder-storms thunder rattling over- 

 head, but not a drop of rain falling. The 

 white mist is not easily observed overhead, 

 where all is light ; but opposite to the sun, 

 under the dark storm-cloud, it is very plain, 

 and must attract attention." 



Fertilization of Plants. Mr. Thomas 

 Meehan discovers in the " sleep " of plants 

 an agent in their self-fertilization. The 

 fertilization of the common Claytonia Vir- 

 glnica had been somewhat of a mystery to 

 him, as, in view of the prevailing theory 

 of cross-fertilization by insect agency, this 

 plant ought not to be a self-fertilizer ; but 

 from repeated observation he was satisfied 

 that no insects had visited plants that had 

 yet seeded abundantly. Watching the pro- 

 cess of fertilization, he found that the sta- 

 mens on expanding fell back on the petals 

 expanded during daylight. At night, when 

 the flower closed, the petals drew the an- 

 thers up in close contact with the pistils. 

 Cross-fertilization could be accomplished 

 by insects if they visited the flower, but 

 they did not, and actual fertilization only 

 occurred in this way. In many cases, es- 

 pecially late in the season, the stamens re- 

 curve so much as to be in a measure doub- 



led up by the nocturnal motion of the 

 petals. The anthers were not drawn into 

 contact with the stigmas in these cases, and, 

 as a result, the flowers were barren. 



In the Ranunculus bulbosns, our com- 

 mon buttercup, in the evening following 

 the first day's expansion of the young flow- 

 er, the immature anthers and the young 

 stigmas would be found covered with pol- 

 len-grains. The inference would generally 

 be, that this had been carried there by in- 

 sects. But, as he had been especially on 

 the lookout for insects as visitors to the 

 buttercup, and feeling sure that none of 

 any consequence had been to them, he ex- 

 amined these flowers carefully, and found 

 that, on the first expansion of the flower, a 

 single outer series of stamens burst their 

 anther-cells simultaneously with the expan- 

 sion of the flower, and, by contracting the 

 cell-walls, ejected the pollen to the smooth 

 petals, from which it easily fell to the im- 

 mature anthers and stigmas, when the flower 

 closed for the night. 



Knowing that another species of butter- 

 cup, the Ranunculus abortivus, had fixed 

 spreading petals which did not close at 

 night, and which, though with compara- 

 tively large nectariferous glands full of a 

 liquid secretion, was wholly neglected by 

 insects, and yet had every flower seeding 

 profusely, he was anxious to find, in view 

 of his other discoveries, how these were 

 fertilized. Visiting a wood after twilight, 

 to ascertain if any nocturnal insects visited 

 them, he found that, though the petals did 

 not close at sundowu, the slender pedicles 

 drooped, inverting the flower, and in this 

 way the pollen found its way from the pet- 

 als to the stigmas without any difficulty 

 whatever. 



Functions of the Root-Hairs of Plants. 



In an article published in the Gardener's 

 Monthly, Prof. B. C. Halsted points out the 

 functions of the " root-hairs " of plants. 

 These so-called root-hairs are thread-like 

 structures, consisting of elongated surface- 

 cells of the root. These hairs absorb water 

 out of the soil either by capillary attraction, 

 or by the process of diffusion, or by osmotic 

 action. It is a well-known fact that porous 

 bodies absorb liquids to a greater or less 

 extent. A dry cloth hung so that one 



