98 



HARDWiCKE'S SCIENCE-GOSSIP. 



whom they are submitted, inasmuch as they either 

 have to risk their reputation for accuracy, or to 

 appear uncourteous by refusing to have anything 

 to do with such specimens. 



To begin at the beginning, how rarely do we find 

 the embryo of any species represented in a collec- 

 tion, of dried plants. It ought to be there, not 

 only as essential to the complete presentment of 

 the history of the species, but as in Certain cases 

 indicating relationships which are not apparent 

 ■when the plant is more advanced. Those who 

 have not observed them would be surprised to find 

 how much variety of form exists in the cotyledons 

 alone, from the fleshy cotyledons of many of the 

 Leguminosae, the Horse-chestnut, &c., to the foli- 

 aceous ones, or seed-leaves, of other plants. 

 Among the latter may be noted and compared the 



Fig. 63. Lime (Tilia europaa). 



lobed or palmate cotyledons of the Lime (fig. 63), 

 the glossy dark -green somewhat kidney-shaped ones 

 of the Beech (fig. C4), and the pinnatifid ones 

 of the common garden Cress {Lepidium sativum), 

 the obcordate ones of the Mustard or Radish, the 

 long narrow thin ones of the Sycamore (fig. G5), 

 the sinuous or corrugated and bilobed ones of the 

 Walnut, — and many more which will occur to the 

 observant reader, or which may be collected by any 

 one who will take the trouble to watch the ger- 

 mination of plants. And by making such collec- 

 tions, unexpected discoveries may aiise, which will 

 yet further confirm what has been said about the 

 variety in form and structure even in these begin- 

 nings of growth. Plants which are, on account of 

 their general affinities, reckoned among the dicoty- 

 ledons, may be found on investigation to have 

 but one cotyledon, as Dr. Dickson observed to be 



the case with two of our Butterworts, Pinguicula. 

 vulgaris and P. gmndiflora, the third species, P. 

 lusitanica, being dicotyledonous; or even to be 

 acotyledonous, as is the case with the Dodder 

 {Cuscuta). In the latter-named genus, it is of im- 

 portance to collect young specimens, as showing 

 that the plant, although parasitic as soon as it 

 comes in contact with a suitable foster-plant, is of 

 independent origin. A search among young plants 

 will no doubt lead to the discovery of some abuor- 



Fig'. 64. Beech (Fagus sylvuticus). 



malities, such as the tricotyledonous embryos lately 

 discussed in Science-Gossip. Of some plants, 

 such as the Furze, the true leaves can only be 

 found at an early stage of growth ; in others, much 

 variation may be noted in many points between the 

 first leaves and the more perfect ones which suc- 

 ceed them ; some, as the Holly, at once developing 

 leaves similar to those which arc produced through- 

 out the life of the plant, and others going through 

 many modifications before the ultimate shape is 

 attained, as in the Ash, Elder, Ivy, Maple, &c. 



The roots or rhizomes also require to be much 

 more fully represented and carefully collected than 

 is usually the case. In every instance where the 

 size of the plant does not prevent, the subterranean 



