NOTES. 



287 



ing which produce secretions of slime, or by 

 the presence of cells containing crystals of 

 oxalate of lime. The operation of these 



> agencies is associated with the action of se- 

 cretory organs, or glandular processes, caus- 

 ing a tendency of particular substances to 

 certain points. The cells forming the trans- 

 parent points probably have some particu- 

 lar significance in connection with the life 

 of the leaf, for their occurrence is so uni- 

 form in particular species that they become 

 distinguishing marks by which the species 

 is known. So, also, the presence of raphides- 

 cells (cells containing needle-shaped crystals 

 of oxalate of lime) is constant in some fam- 

 ilies, as in the Dioscoreas, smilaxes, and Tac- 

 cacece, although the transparent points are 

 rarely observed in their leaves. Cells con- 

 taining resin or ethereal oil are constant in 

 at least three species of pepper, and in all 

 of the Monimiacece. Interior glands, with 

 brown radiating crystals of resinous sub- 



. stance, are characteristic of the Myrsiniece, 

 and are wanting in only a few species. The 

 anatomical structure which leads to the pro- 

 duction of these points evidently has some 

 systematic importance, and should not be 

 overlooked in the determination of the char- 

 acteristics of the different groups. 



NOTES. 



In Dr. Pyburn's article on "A Home-made 

 Telescope," in the last (November) number 

 of the " Monthly," page 86, seven lines from 

 the bottom, the diameter of the thirty-inch 

 roller is given as " two and five eighths 

 inches " ; it should read " one and five eighths 

 inch." 



Professor Baird announces the final 

 solution of the problem of the culture of 

 oysters from artificially impregnated eggs. 

 The Government station at Stockton, Mary- 

 land, had in September last many millions 

 of young oysters three quarters of an inch 

 in diameter, which had been hatched from 

 eggs artificially impregnated forty-six days 

 before. Oyster's had already been artifi- 

 cially impregnated by Dr. Brooks, but the 

 practical difficulty existed of preventing the 

 young oysters, which could pass through the 

 meshes of the most closely woven fabrics, 

 from escaping. 



Our Educational Bureau is circulating 

 an excellent paper from an address given to 

 school-teachers in Switzerland on how nat- 

 ural science should be taught. The object, 

 it says, should be, not to fill the mind with 



facts, but to bring all the scholars, includ- 

 ing the slowest ones, to discover and observe 

 facts for themselves. Books should be lit- 

 tle used, and nothing about an object should 

 be taught without the object being before 

 the class. The next lessons should be in 

 describing the facts observed, with the help 

 of drawing, if possible. Plants should be 

 chosen first, then animals of different class- 

 es, then minerals, with observations of me- 

 chanical and afterward of chemical effects 

 upon them. But the bare making of collec- 

 tions should not be particularly encouraged. 



The "United States Hay Fever Asso- 

 ciation" held its tenth annual meeting at 

 Bethlehem, New Hampshire, during the last 

 week in August. The speeches made and 

 the experiences related indicate that the 

 cause and specific cure for the uncomfort- 

 able disease in question are yet to be found. 

 A particular preparation which has been 

 much recommended was, by nearly general 

 consent, pronounced of no value as a reme- 

 dy. Much information regarding the mal- 

 ady had been gathered by Dr. Geddings. 



The lowering of the freezing-point of 

 water by increased pressure is frequently 

 illustrated by the experiment of Bottomley, 

 which consists in throwing across a cake of 

 ice a wire weighted heavily at both ends. 

 The wire slowly sinks through the cake, the 

 ice melting beneath it and freezing above 

 it. Professor Guthrie, at a meeting of the 

 Physical Society in London, has stated his 

 belief that the wire conducts heat to the ice 

 from the atmosphere, and that therefore 

 the experiment does not illustrate the fact 

 above mentioned. A silk cord weighted to 

 the same amount as a wire will not cut 

 through a block of ice. 



The death is recorded of Hermann Mtil- 

 ler, of Lippstadt, one of the most industri- 

 ous and distinguished scientific investigators 

 of the day. His specialty was the fertiliza- 

 tion of flowers by insects, in which subject 

 he was regarded by naturalists as the high- 

 est authority. He was the author of two 

 books on the subject, " Die Bef ruchtung der 

 Blumen durch Insecten " (" The Fertilization 

 of Flowers by Insects "), recently translated 

 into English, and " Alpenblumen, ihre Be- 

 f ruchtung durch Insecten" ("Alpine Flowers, 

 their Fertilization by Insects ") ; of an article 

 in Schenk's " Handbuch der Botanie," and of 

 frequent contributions to the German peri- 

 odical " Kosmos." 



Ernest Ingersoll observes, in the 

 " American Naturalist," that if we judge by 

 the standard of their possessing a conven- 

 ient currency, the American Indians must be 

 ranked high among barbarians in point of 

 advance toward civilization. They had in 

 their wampum a regular money of recog- 

 nized value. It marked an advance upon 



