HARDWICKE'S SCIENCE-GOSSIP. 



porcupine's quill, display the branches of the weed 

 in a natural manuer, as the glass is cautiously drawn 

 out of the water. Put it in a slanting position for 

 a few minutes to drain, and then, having placed the 

 glass on apiece of blotting-paper, cover the specimen 

 with a smooth piece of fine cambric, and then place 

 a piece of blotter on the cambric, employing very 

 gentle pressure, while another specimen is being 

 prepared for another glass. Change the blotting- 

 paper frequently, but use very little pressure, and 

 do not remove the cambric until the plant is quite 

 dry, which it will be in a couple of days. Remove 

 the cambric very gently, and clean away the saline 

 particles which remain on the glass in all directions 

 by means of a finely-cut stump, and finally brush 

 gently with a camel's-hair pencil around and be- 

 tween the branches of the plant, but touch the 

 specimen as little as possible. I have kept plants 

 so prepared on glass wrapped up iu tissue-paper for 

 years before they were mounted in balsam. I need 

 hardly say that fresh-water algse must be cleaned 

 and mounted in fresh water, whether they are to 

 be mounted on glass or paper. Unless the mani- 

 pulator be skilful in laying on the balsam and 

 placing the glass cover on his specimens, he had 

 better commit his preparations to the care of 

 Messrs. Topping & Son, Mr. J. Bond, or Mr. Nor- 

 man, the addresses of whom may be obtained from 

 Messrs. Carpenter & AVestley, 2i, Regent-street, 

 London. 



When algpe are required to be prepared loose and 

 dry, my plan is first to provide myself with small 

 sheets of fine cartridge-paper, and having soaked 

 them well in pure salad oil, let them drain well, and 

 afterwards dry them in the sun for a day or two. 

 The specimens, which must be cleaned and washed 

 as already described, may then be mounted on the 

 oiled papers in the clearly-strained sea or fresh 

 water, and covered with cambric and blotter, and 

 subjected to pressure, and the oftener the blotting- 

 paper is changed the sooner the plants will lie 

 ready. Upon removing the cambric cover, the 

 specimens will be found adhering either to it or the 

 oiled paper, from either of which they may be easily 

 removed by means of the fingers or a pair of forceps. 

 They may then be mounted in balsam at once, or 

 placed flat between sheets of writing-paper, and if 

 kept from the light, will retain their exact condition 

 and colour for years. 



In preparing seaweeds for mounting in Canada 

 balsam, it is of course always desirable to have 

 specimens fresh from the sea ; but when these are 

 not obtainable, nearly every mounted plant, with 

 the exception of the gelatinous species, and a few 

 others among the red subdivision, may be removed 

 from paper by soaking them well in water, and 

 employing a porcupine's quill to detach them — a 

 process which requires time, careful manipulation, 

 and considerable patience. W. H. Gkattann. 



ON WHITE AND OTHER VARIETIES 

 OF FLOWERS. 



THE following species have been found by me of 

 a clear white, wholly untinged with colour, 

 though they arc distinctly, some very strongly, 

 coloured in their ordinary state : — Cardamine pra- 

 tensis, frequently ; Viola odorata, known, of course, 

 to every one; Malvu moschata, once only, near 

 Oswestry ; Epilobium montanum, seldom ; Campa- 

 nula rotundifolia, occasionally ; Erica tetralix, I 

 have white specimens, wild, but the locality, though 

 certainly British, is unknown ; Solatium Dulcamara, 

 Tunbridge Wells, and near Oxford ; Digitalis pur- 

 purea, ill Denbighshire; Pedicularis sylvatica, on 

 Tunbridge Wells Common ; Scutellaria galericulata, 

 around Abingdon; Polygonum persicaria, rarely, 

 Colchicum autumnale, in Sweeney meadows," near 

 Oswestry. None of the many Floras I have ex- 

 amined speak of a white variety of this plant. 

 Flowers of pure white, however, occur abundantly 

 among the profusion of others of ordinary hue which 

 constitute the autumnal adornment of these low- 

 lying fields, but are not distinguished from them, . 

 so far as I could trace, by any other characters ; . 

 Agraphis nutans, occasionally. Other variations in 

 tint which I have noted are of some interest. Ane--- 

 none nemorosa, as it usually occurs, is white, but . 

 with a strongly-marked purplish exterior, as if in- 

 dicating a union between dark sepals and uncolouredt 

 petals. The petals are, however, in reality, absent- 

 The purple tint is, of course, a compound of red and 

 blue. I have found the flower vary in the one 

 direction into the total absence of the purple tinge, 

 and, consequently, to perfect whiteness, and on the 

 other to a development of the purple, that hue, 

 extending even into the interior of the perianth,. 

 This latter variation occurs in numerous degrees^ 

 more or less removed from the original point of 

 departure, and taking two separate courses, accord- 

 ingly as the red or blue constituent of the purple 

 becomes gradually predominant, ending in the pro*- 

 duction on the one side of a rich pink flower from,' 

 which all trace of blue intermixture is absent, and; 

 on the other of the sweet blue, almost azure, variety 

 for which some spots in the neighbourhood of Tun- 

 bridge Wells are noted. All the variations I have 

 named occur around that beautiful inland watering- 

 place, and do not appear to have any particular 

 connection with different soils or situations ; indeed 

 many degrees of hue, from blue and reddish-purple 

 to white, are found in company. The richest and 

 purest pink flowers I found on the noble range of 

 the lower greensand, near Sevenoaks. 



Polygala vulgaris. The variation of this between 

 perfect blue and perfect pink to a nearly perfect 

 white is well known. I have never found a speci- 

 men wholly white, blue being in the so-called white 



