484 



SCIENCE. 



[Vol. I., No. 17. 



we see actuall}' done in sunlight ; and thus 

 whoever can, without altering the quantitj-, 

 eifect this change in the quality of the radia- 

 tion from gas, will add millions to the national 

 wealth. S. P. Langley. 



THE NEW-YORK AGRICULTURAL 

 EXPERIMENT-STA TION. 



Thb weekly bulletins of the New- York experiment- 

 station, althougli " intended to inform the public of 

 progress at the station rather than to give complete 

 results," nevertheless contain some matters of in- 

 terest. 



Seeds. — A series of weighings on light and dark 

 colored seeds of several kinds showed, that, in every 

 case, a hundred dark-colored seeds vs'ere heavier than 

 the same number of light-colored seeds. The dark- 

 colored seeds were also found to contain a larger 

 percentage of seeds capable of germination. Sprout- 

 ing-trials with onion-seed of difierent ages indicated 

 that seed over two years old is of little value. Con- 

 firmation was obtained of the resvilts of Will on tlie 

 regermination of seeds, reported on p. 176 of Sciknce. 

 Out of a hundred kernels of corn, eight germinated 

 for the fifth time after drying in the air. Both field- 

 experiments and sprouting-trials showed a decided 

 suijeriority, as seed, of corn taken from the tips of 

 the ears over that taken from the butts or the middle. 



Potato-culture. — Tire terminal eyes of the potato 

 were found to germinate more promptly and vigor- 

 ously than the basal eyes. The best crops were 

 obtained, and at the least expense of seed, by cutting 

 the potatoes to single eyes, and so cutting them that 

 each eye retained a portion of the tuber extending as 

 far as possible towards the central axis. Each eye 

 may be regarded as the terminal bud of a branch ex- 

 tending from the central stem; and the potato should 

 be so cut that each bud may retain all, or nearly all, of 

 its branch. The conditions favoring the production 

 of potatoes seem to be moisture and coolness for the 

 roots, and warmth and dryness for the tubers. Cul- 

 ture which supplied these conditions, such as ridge- 

 culture, and, still more, covering the seed-potatoes 

 with four or six inches of sand, gave a large increase 

 over level culture. 



Root-development. — By excavation and washing, 

 the development of the roots of several species of 

 plants has been traced. Corn seemed to have two 

 systems of roots, — one of fibrous roots, developing 

 chiefly in the upper and warmer layers of the soil; 

 and the other of coarser roots, passing downward into 

 the subsoil. The hypothesis is advanced, that the 

 former system serves mainly to supply the plant with 

 ash ingredients, and the latter with water, and per- 

 haps nitrogen. Wheat and potatoes appear to be 

 deep feeders, developing their roots more abundantly 

 in the lower and cooler layers of the soil. Tobacco, 

 on the other hand, is a shallow feeder, like corn. 



Feeding-experiments. — A single determination of 

 the digestibility of corn-ensilage gave the following 

 percentage results : — 



Proteine 51.89 



Fat 79.17 



Crude fibre 60.91 



Nitrogen free extract 67.59 



The figures for proteine particularly are lower 

 than those given in Kuhn's tables of digestibility; 

 and the conclusion is drawn, that the process of 

 ensilage has decreased the digestibility of this in- 



gredient. The conclusion is, however, entirely 

 unwarranted; for the figures simply show that the 

 ensilage was less digestiWe than Kiihn's corn-fodder, 

 but show nothing whatever about the digestibility of 

 the corn-fodder of which this ensilage was made. 



A series of feeding-experiments on milk-cows was 

 can-ied out, the fat in the milk being determined 

 chemically, while, at the same time, the butter 

 obtainable from it was determined by actual churn- 

 ing. The interesting result was reached, that, with 

 different rations, the amount of butter fluctuated 

 much more than that of the total fat: in other words, 

 the feeding seemed to make a difference in the com- 

 pleteness with which the butter could be extracted 

 from the milk. A ration of shorts and hay gave the 

 best results in this regard. Other interesting minor 

 results were obtained, but the main object of the 

 investigation is not very apparent from the accoimt 

 given in these bulletins. The coarse fodder was 

 eaten ad libitum, the amount of water drunk was not 

 regulated, and no suflicient data are here presented 

 for a comparison of the different raticnis. It is to be 

 presumed, however, that some of these deficiencies 

 will be supplied in the formal report of the station. 



An analysis of the milk of fatigued cows showed 



that it was quite phenomenal in character, the total 



solids being nearly a third greater than the normal 



amount, and the increase being nearly all in the fat. 



H. P. Armsbt. 



CLASSIFICATION OF ISLANDS. 



A. KiKCHHOFF (Kettler's zeitschr. wissensch. (/eoffr., 

 iii. 169) presents some criticisms on Peschel's and 

 Wallace's work in this direction, and proposes the fol- 

 lowing table. A, FestUindische inseln: a, Abgliede- 

 rungsinseln ; b, Restinseln. B, TJrspriingliche inseln : 

 a, Submarin enstandene vulkanische inseln; b, Auf- 

 schiittungsinseln; c, Nichtvulkanische hebungsin- 

 seln. The first group includes those derived from a 

 continental land-mass, either by submergence or 

 seashore erosion, the latter being uncommon. Its 

 first subdivision (dismemberment-islands?) are found 

 along the borders of existing continents, and are 

 very numerous. The second subdivision (remnant- 

 islands?) would include the last surviving sum- 

 mits of a drowned continent; but no examples are 

 surely known, unless those of the Antarctic Ocean 

 belong here. These continental islands might be 

 of volcanic rocks, for the higher points of many exist- 

 ing continental districts are of volcanic origin: they 

 are not necessarily of varied geological structure, 

 as described by Wallace. Witness the monotonous 

 low quaternary islands along the German seacoast. 

 And, while it is true that land mammalia and am- 

 phibia are wanting on islands of the second group, 

 it is an error to say, with Wallace, that they are 

 always present on those of the first. Wallace recog- 

 nizes that elevation, after a complete though short 

 submergence, would reveal the island bereft of its 

 earlier continental fauna, but finds no examples of 

 such a result. Kirchhoff adduces the Halligen 

 Islands of the North Filsian group as such examples ; 

 for their low surface is frequently submerged by 

 high winter tides, leaving only the huts crowded on 

 artificial mounds above water. They have no mam- 

 mals (except the domestic); moles are unknown in 

 their green meadows; nor have they toads or frogs. 

 Larger examples of the first group are seen in Green- 

 land and the ai'chipelago north of British America; 

 in the West Indies, once connected with South 

 America, Florida being of comparatively modern ex- 

 tension towards Cuba; New Guinea; and Borneo. 



