Jan. 1, 1865. J 



SCIENCE-GOSSIP. 



17 



rise in Tibet from lakes full of fisb, but have uoue (at 

 least during the rains) in that I'apid part of their 

 course from 10,000 to 14,000 feet elevation ; below 

 that fish abound, but invariably of different species 

 from those found at the sources of the same rivers. 

 The nature of the tropical ocean into which all the 

 Himalayan rivers debouche, is no doubt the proxi- 

 mate cause of the absence of Sulmonidcc — Hooher^s 

 H'malmjan Journal. 



B T A IT Y. 



Sheep Sokkel in New Zealand.— One of the 

 greatest pests of this country (on the cultivated 

 lands) is the common English Sheep-sorrel {Riimex 

 acetosella), called by the natives the red sorrel, and 

 said by them to be a native of Tasmania. This 

 plant spreads with singular rapidity, its roots 

 forming a perfect mat, and the smallest fragment 

 throwing up a stem. Where it is present in the 

 ground scarcely any of the ordinary crops can be 

 obtained. All the usual processes of cultivation, 

 such as fallows, &c., utterly fail even to mitigate 

 the evil, and farmers were in despair, until it was 

 found, that in the " struggle for existence," even 

 this weed could not make head against the greater 

 vigour of the white clover. I have seen hundreds 

 of acres of brokeu-up land so completely over- 

 grown with this plant, as to appear like a uniform 

 red patch in the landscape, but upon which, at the 

 end of two years, after it had been "laid down" 

 wath white clover and Italian rye-grass (which by 

 itself would have done no good), scarcely a speci- 

 men of the sorrel could be found. — Travers, in. 

 Natural History Review. 



Most Perfect Plants. — Those planls are 

 most perfect, in which the organs discharging 

 different functions are most distinct both in 

 position and structure. The thalloid fronds (of 

 CactaccEe) and the hypoblastoid eml)ryos of En- 

 dogens indicate a lower degree of organization. 

 Plants which have the stamens and pistils either 

 naked or in the axil of an unmodified leaf {Naias, 

 Hippuris, Callitriche) are inferior to those whose 

 flowers are never complicated. Diclinous flowers are 

 lower in position than those Vi'hich are hermaphro- 

 dite; ternary verticils lower than quiniary, spirally 

 arranged floral organs lower than those which are 

 verticillate, polypetalous flowers lower than gamo- 

 pefalous, apocarpous ovaries lower than syncarpous, 

 airopous ovules lower than those which are inverted, 

 homogeneous embryos lower than those v/hich are 

 fully developed. Trees and shrubs are more com- 

 mon among imperfect pianis. In the lower ordeis 

 flowers are very numerous, in the higher the 



number of seeds produced by each flower is very 

 great. Yellow and green colours in the flowers of 

 the lowest rank are changed into red or white in 

 those of a higher order, and in the highest plants 

 the colour of the flower is generally blue.—/. G. 

 Agardh. Thoria Sysfematis Plantarurii. 



A Horse-chestnut Tree.— Dr. Davy read a 

 paper at Bath on the horse-chestnut ; will any one 

 read a paper on a horse-chestnut ? The tree stands 

 on a flat stone. Its root grows up through the air 

 for 7 feet, turns over a wall, and descends 7 feet 

 into the eartli. So that the root passes for 14 feet 

 through the air before it enters the earth. The 

 celebrated Dutrochct, by experiment, convinced the 

 still more celebrated De Caudolle, and all European 

 vegetable physiologists, that roots will only grow 

 straight downwards. On this, I set to work to show 

 that they will grow in any direction in which they 

 can find food. If any one doubts this fact, let him 

 inspect my tree, which is now twenty-one years old. 

 In imitation of Dutrochet's beautiful experiment, I 

 placed a great variety of seeds (single as well as 

 double) in flower-pots, suspended them upside down 

 on wire-work, and watered them from above. Each 

 seed sent a tap-root down into the air, which died ; 

 but the branch roots (as I have named them) and 

 the plants grew, and corn ripened in this way. Bat 

 cuttings placed upside down, though they grew and 

 bore fruit for years, showed no root below. I thus 

 blundered on the fact that every seedling has a tap- 

 root, whose downward determination nothing can 

 pervert, a provision and contrivance for the fixing 

 of the plant, and a beautiful proof of the design of a 

 Creator. But the downv»'ard tap-root is as peculiar 

 to tlie seedling as the " seed-leaves " are, and all 

 branch roots will grow in all directious. I preserved 

 one horse-chestnut by placing it on a flat stone, 

 and replacing the liower-pot with a chimney-pot iVJl 

 of earth, and, by degrees, raised a column of chimney- 

 pots. I then built up a column of earth on the 

 opposite side of the wall, turned the roots into it, 

 and when they were established in the ground, I 

 took away the two columns of earth. I think that 

 Virgil's tap-rooted Esculus is the horse-chestnut. 

 Yirgil mentions it as distinct from the quercus and 

 castanca, and Ovid as distinct from iliQfagus and ilex. 

 It is, then, a feat to make its radix tend to heaven 

 instead of to Tartarus. 'With regard to the name 

 from Esca, it is true that neither man, horses, nor 

 pigs will eat horse-chestiuits, but sheep, covins, and 

 deer are ravenously eager for them.— 6'o/. Green- 

 wood, ill Athenceiun. 



Plants Rooting in tub Soil. — Plants them- 

 selves send dovrn their roots naturally to a depth 

 v/liich, strange to say, is so little known as scarcely 

 to be credited. In the case of beans, tui-uips, ar;d 

 red clover, we are ■familiar with the fact, that their 



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