HARDWICKE'S SCIENCE-GOSSIP. 



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died when constantly exposed to direct sunlight, 

 whilst some kept on a shelf in the somewhat dark 

 corner of a room was beautifully green and fresh the 

 whole of the summer, decaying in autumn, and 

 reappearing from the sand with bright green slender 

 simple stems in January this year. Charas are like 

 many other plants, in the best condition when their 

 fruits are ripe, and in the before-mentioned species 

 this is early in the year. Such species as Chara 

 fragilis, which ripens its fruit in July or August, will 

 no doubt then be in the best condition ; but my 

 experience after some years of collecting is, that 

 charas may be looked for with the best prospect of 

 success in early spring, before the coarser vegetation 

 which fills many of our ditches has started into 

 growth. — Thomas Birks, jun., Goole. 



Leontodon Taraxacum. — I think both the 

 classification and description given by A. II. Svvinton 

 liable to mislead and confuse younger botanists in 

 their attempts at identification. To begin with, the 

 commonly accepted name of this genus is Taraxacum 

 Leontodon. The full name is Taraxacum officinale. 

 Then the varieties are not major, minor, andpalnslris. 

 There are four varieties, as follows (vide "London 

 Catalogue," last edition, and Sowerby's "English 

 Botany," 3rd edition) with the separating characters 

 for each ; 1. T. Dcns-leonis. Leaves bright green. 

 Inner phyllaries simple at apex ; outer ones narrow, 

 recurved. 2. T. erythrospermnm. Leaves dull green. 

 Outer phyllaries lanceolate, spreading. 3. T. loevi- 

 gatum. Leaves dull green. Outer phyllaries ovate- 

 lanceolate, erect. 4. T.palustre. Leaves often almost 

 entire, usually sinuo-dentate with the lobes ap- 

 proximating. Outer phyllaries ovate, acuminate, and 

 more adpressed than in 1, 2, or 3. Varieties 2 and 3 

 have a tiny ligulate appendage below the apex of the 

 inner phyllaries, but may be separated as above, and 

 by the fact that the achenes in var. 2 are dark red, 

 and in var. 2 olive-coloured. The term "leaflets " is 

 wrongly used here. The leaves are simple, with 

 variously-shaped lobes. Var. 4 is not usually in 

 flower until late summer. — H. W. S. Worsley-Benison. 



Flowers of Duckweed. — I took Lemna minor 

 and L. polyrrhisa with flowers at Beccles last August, 

 and L. gibba and L. trisuka near Willesden a week 

 or two later, the former with a very few flowers here 

 and there. L. triscnla I have seen in flower in 

 Chepstow, Monmouthshire.— //. W. S. Worsley- 

 Benison. 



Flowers with Double Colours.— Mr. Her- 

 mann Muller has very clearly explained why such 

 flowers as the common lungwort {Pnlmonaria offici- 

 nalis), and others of the same natural order, have 

 two colours, red and blue. The former colour is 

 generally assumed first, and the latter as the flowers 

 get older. He proved by examination that all the 

 blue flowers of the lungwort were empty of honey, 



and the stigmas of their pistils were supplied with 

 pollen. Mr. Muller concludes that the blue colours 

 of the older flowers of the lungwort, whilst increasing 

 the conspicuousness of the clusters of flowers, at the 

 same time indicate to intelligent bees, such as 

 anthrophora, to which flowers they should restrict 

 their visits, to their own as well as to the plants' 

 profit. The more intimately we are acquainted with 

 the biological relationships of flowers, the more do- 

 we discover that " every freckle, streak, and stain" 

 has a distinct meaning and bears some active relation- 

 ship to the well-being of the plant. In many flowers 

 belonging to other orders the colours change as the 

 flowers get old, as in hawthorn blossom and the little 

 celandine, and these faded colours may also indicate 

 to insects where their visits would be unnecessary and 

 useless. 



Flowers of Pollard Willows.— Can any 

 reader kindly tell me if there is any reason for the 

 great preponderance of pistillate plants amongst 

 pollard willows ? I have examined a great number, 

 and have failed as yet to find a single staminate one- 

 Is there any preference for the one as being more 

 suitable for the purpose of pollarding ? Many of the 

 trees were very old ones. — C. D. B. 



The Fertilisation of Willows.— Having, 

 frequently heard it stated that the bee visited only 

 the male catkins of the willow, I have, during the 

 last few weeks, carefully observed the behaviour of 

 these insects in their dealings with this plant. 

 Fringing the Ouse embankment at Bedford, is a 

 large growth of Salix triandra, and close by there 

 are extensive beds of S. viminalis. The male 

 catkins are yellow and decidedly attractive, but the 

 females are green and less conspicuous. The bees 

 also show the superior attracting-powers of the male 

 over the famale catkins. Two or three times a week 

 for the past month I have visited these willows, and 

 only on one of these occasions have I seen the bees 

 visit the female catkins, and then only because no 

 males were near. Both sexes produce nectary 

 glands, and the question arises what can be the 

 object if the insect rarely visits the female catkins? 

 The view I have formed (correctly or incorrectly 

 I know not) is as follows : Amentiferous plants 

 dependent entirely upon the wind for fertilisation 

 have pendulous catkins, but in the willow the 

 catkins are upright and elastic. The humble-bee 

 is a heavy insect, and it almost invariably mounts 

 to the summit of the catkin which is borne down 

 by its weight. On the bee taking flight, the 

 catkin springs suddenly to its original position, and 

 thus shakes out the pollen-dust in the male, and 

 further distributes that which may have lodged in 

 the scales of the female catkin — both of which 

 processes would be advantageous to the plant. 

 The presence of the nectary-gland in the female 



