HAllDWICKE'S SCIENCE-GOSSIP, 



99 



and subaqueous parts should be carefully procured 

 and preserved. Dr. Trimcn has lately directed 

 attention to the conn-like tubers of the Water Plan- 

 tain (Jlisma)* closely resembling those of the 

 Arrowhead {Sagittaria), which have been described 

 and figured by Nolte, but " do not seem to have 

 been observed, or at least properly ^mderstood, in 

 this country. They are buds remaining dormant 

 through the winter, and containing a store of 

 nutriment, to be employed in the development of 

 the new plant from the tuber in the next year." 





Fig. 65. Sycamore {Acer pseudo-platunus). Showing Coty- 

 ledon, and fii-st and second pair of leaves. AU drawn by 

 Miss Giles, trom specimens lent by Mr. O. A. Favvis. 



Similar bulbs are developed by the Progbit 

 {Eydrocharis) . In determining many grasses and 

 rushes, it is of importance to ascertain whether the 

 rhizome is creeping or csespitose, and it is therefore 

 essential to collect good specimens. In the case of 

 such plants as the Coral-wort {Dentaria bulbifera) 

 and Tooth-wort {Lathrcea squamarid), the root- 

 stocks are eminently characteristic. Of such para- 

 sites as the Broomrapes {Orobanche), some care is 

 requisite in obtaining specimens in which the con- 

 nection between the parasite and its foster-plant 

 may be preserved and shown. Tiie absence or pre- 

 sence of tubers should also be noted, and if present, 

 they must be represented. 



Passing on to the leaves, we may note the im- 

 portance of obtaining in every case the root-leaves 

 of each species. These are often very different in 

 form from the stem-leaves, as in such species as 

 the Harebell {Campanula rotundifolia), Pimpinella, 



\_ _ • Journal of Botany, vol. ix. p. 306. 



Saxifraga, the Earth-nut {Bimium flexuosum), and 

 many more; in some instances, as in the Jersey 

 Bugloss {Echiiim plantagineum^, they at once cha- 

 racterize the species. Still more important arc 

 these lower leaves in the case of water-plants : in 

 the Arrowhead {Saglttaria), for example, they are 

 narrow, and resemble those of the Bur-reed {Spar- 

 ganinm) ; and in the Water Plantain {Alisma 

 Plantago), the submerged leaves are equally dif- 

 ferent from those which rise out of the water. 

 This difference is still more noticeable in the case 

 of the aquatic Ranunculi, where a knowledge of 

 the submerged leaves is essential to the discrimina- 

 tion of the various forms or species. 



Where practicable, the whole plant should be 

 collected for the herbarium ; but when, from its size, 

 this cannot be accomplished, leaves from the root, 

 the centre of the main stem, and the lateral 

 branches, should be taken. As to the stem itself, 

 that must be represented : in the Buhl, indeed, 

 it is essential. "To judge properly of a bramble 

 from a preserved specimen," says Professor 

 Babington, " we require a piece of the middle 

 of the stem with more than one leaf; the base 

 and tip of the stem are also desirable, like- 

 wise a piece of the old stem with the flowering 

 shoot attached to it ; the panicle with flowers, and 

 the fruit. We likewise want to know the direction 

 of the stem throughout, of the leaflets, and of the 

 calyx ; also the shape of the petals and the colour 

 of the styles : a note of these should be made 

 when the specimen is gathered." 



Passing on to the flowers, we shall find it neces- 

 sary to represent them in almost every stage, from 

 the bud to the perfecting of the fruit. It is of 

 course in most cases possible to select an example 

 in such a state as to show upon the same plant 

 buds, flowers, and fruits ; but where this is not the 

 case, each of these particulars must be supple- 

 mented by additional specimens. The turn which 

 botanical investigation has recently taken towards 

 the study of the phenomena connected with fertiliza- 

 tion has given the collector another subject to which 

 his attention may be profitably directed. It has 

 been observed that in some plants the stamens are 

 developed before the pistils, in others the pistils 

 are matured before the stamens ; while in yet a 

 third set, stamens and pistils are simultaneously 

 perfected. These three groups of plants are termed 

 respectively protandrous, protogynous, and synacmic, 

 and a very little observation will show that example 

 of each are suificiently common. 



Then in dioecious and monoecious plants, both 

 male and female flowers must be collected ; and in 

 some cases, as in the Willows, four specimens are 

 necessary to the complete presentment of the 

 species, showing respectively the male and female 

 catkins, the leaves, and the fruit. Some plants 

 produce two distinct forms of blossom, as is 



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