3° 



SCIENCE- G OS SIP 



noted blossoms in the first week of June. Mr. 

 Burkill states that they " do not seem to profit by 

 their early flowering." I think, however, that by 

 their early fruiting they gain a whole season, for 

 the ripe fruits are now shedding, and may be 

 germinating, as is the case with willows, this 

 being a fact well known to the raisers of willow 

 hybrids. — Eleonora Armitage. Badnor, Boss, 

 Herefordshire, May 16th, 1901. 



Eichmond Park Plants. — This locality will 

 f urnish the student of field botany with a few local 

 and interesting plants. About the Pen ponds the 

 shoreweed (JAttorella) is abundant, and forms a 

 matted growth. Here also grow the lesser water- 

 plantain (Alisma ranunculoides), both species of 

 skull-cap, the smaller Scutellaria minor, and the 

 more beautiful S. galericulata, and with these a 

 minute spike rush (Eleocharis aeicidaris), which is 

 said to flower but little except in dry seasons. It 

 was flowering there last autumn. Chief among the 

 aquatic plants found in the Pen ponds is Limnan- 

 themum peltatum. This beautiful plant when found 

 in artificial waters is always subject to the suspicion 

 of having been purposely introduced, and this may 

 have been the case here, though the fringed water- 

 lily is so much at home in the valley of the Thames 

 that this locality may well be a natural habitat. 

 About the Pen ponds and elsewhere may be found 

 large clumps of Juncus diffusus, a rush which is of 

 interest as being the hybrid offspring between 

 J. glaucus and J. effusus. It is of a taller growth 

 than J. glaucus, and, moreover, is green in colour. 

 In character it is fairly intermediate between the 

 two parent species, the stems being more distinctly 

 grooved than in J. effusus, and less so than 

 J. glaucus. Generally the ovary has failed to 

 enlarge, but in some flowers growth has occurred 

 to a small extent, and then ceased, no seeds being 

 perfected. This rush may easily be detected by 

 its sterile condition. Other plants to be found in 

 Richmond Park are Viola ericetorum (the dog 

 violet), Sagina ciliata, and Myriophyllum alterni- 

 Horum. — C. E. Britton, 35 Dug dale Street, S.E. 



The Grass Vetch.— This interesting and 

 "beautiful plant is seldom now met with in the 

 neighbourhood of the metropolis. In some parts of 

 Kent, however, Latliyrus nissolia is common, 

 •especially near Sevenoaks, where it may be found 

 growing abundantly, for some miles, by the road 

 between Hubbard's Hill and Leigh. — C. E. Britton. 

 35 Bugdale Street, S.E. 



Viola Odorata x Hirta. — Is there good 

 -evidence that V. permixta Jord., and V. sepincola 

 Jord., are hybrids '.' I find the one with pale greyish- 

 blue petals and one with dark blue flowers, perhaps 

 darker than V. odorata. Both forms produce freely 

 runners and apetalous flowers. — Thomas Hilton, 

 16 Kensington Place, Brighton. 



ANSWERS TO CORRESPONDENTS. 



Hon. Mrs. H. (Bletchworth). — The specimen 

 sent for naming is Alliumi victorialis, which belongs 

 to an extensive genus, with a distribution over the 

 northern temperate regions of both hemispheres. 

 Some of the species have expectorant and sedative 

 qualities, but these are reduced to a minimum in 

 A. victorialis. The question of commensalism, 

 which you suggest as existing between this and 

 Ornithogalum umbellatum, is an interesting one, 

 which would take some years of careful observation 

 to rightly determine. — J. S. 



STRUCTURAL and PHYSIOLOGICAL BOTANY. 



CONDUCTED BY HAROLD A. HAIG. 



Recent Cytology. — In the '-Journal of Applied 

 Microscopy " for March there is an account of 

 some work by Mr. Timberlake on "The Develop- 

 ment of the Cell-plate in Higher Plants," under- 

 taken to determine in detail the exact sequence 

 of events during division of the cell-body. He 

 finds that the chromatin of the nucleus is the real 

 centre for the formation of kinoplasmic fibres, and 

 that after having formed fibres round the nucleus 

 as a centre the kinoplasm takes part in the process 

 of nuclear division, and later divides the cell by a 

 part of the fibres being transformed into a mem- 

 brane which becomes, in splitting, the plasma- 

 membranes of the daughter-cells. Also, the relation 

 of the carbohydrate substance to the process of 

 division seems to show that the material for the 

 formation of the cell-wall is held in reserve form 

 in the protoplasm before it is actually needed for 

 the process of wall-formation ; and there is probably 

 some evidence for the hypothesis that the nucleus 

 forms the cell-wall substance. 



Vitality of Seeds. — The much-vexed point 

 with regard to the vitality of seeds is so often 

 made a matter of investigation that one can hardly 

 take up any paper on botanical subjects without 

 coming across something relating to it. There 

 have been some interesting investigations made in 

 connection with the germinating pow T er of seeds 

 which have been kept for a long time under 

 peculiar conditions. It was, for instance, found by 

 the Italian botanist Giglioli that of sixty seeds of 

 lucerne kept from 1878-1894 in absolute alcohol, 

 forty germinated when removed from that liquid 

 and placed under favourable conditions. Moisture 

 was, of course, carefully excluded from the seeds 

 during their preservation. One is almost inclined 

 to think that the hard testa of the lucerne seeds 

 would prevent the alcohol from permeating the 

 whole substance of the seed ; but, on the other 

 hand, it is well known that the protoplasm in the 

 cells of the embryo, whilst in the seed, contains 

 very little water, and that probably in the form of 

 water of constitution. The protoplasm of ordinary 

 cells from an adult plant is entirely killed by 

 absolute alcohol ; is in fact, as we term it, "fixed," 

 since any proteids present are coagulated ; and this 

 fixing having once taken place, no vital phenomena 

 can henceforth continue. It may be different with 

 protoplasm in seeds ; but, as was mentioned above, 

 one cannot help thinking that the preservative 

 fluid does not in all cases reach the cells of the 

 embryonic plant. Perhaps some of our readers 

 can give an explanation of this rather interesting 

 point. 



Modifications of Structure by Freezing 

 and Plasmolysis.— Bj r reduction of temperature 

 below 0° C. there is produced in the interior of 

 the nucleus a change resulting in the separation 

 out of two substances, which are respectively the 

 nucleohyaloplasm and the water of constitution. 

 The former takes on the appearance of a wide- 

 meshed network ; the latter collects into vesicles 

 which transude ultimately through the nuclear 

 membrane. Plasmolysis brings about exactly the 

 same changes, the water of constitution diffusing 

 out in just the same manner. (" Cosmos," No. 841, 

 p. 315.) Both these processes seem thus to have 

 a disorganising effect upon the nucleus, destroying 



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