102 



BOTANY. 



however, by makinpr a large number of very tbin sections of tbe whole 

 leaf (by placiug it Ijeiween two pieces of elder pitli), when it will be 

 ;ound that in some cases stomata have been cut through in the man- 

 ner shown in Fift. 93. 



(6) Examples may be obtained from any of tlie liigrher plants, but 

 those which are of a firm texture and have a smooth epidermis are 

 liestto begin with — e.g-.t^ie hyacinth, tulip, the lilies, many grasses, 

 luclisia, lilac, etc. 



(c) Weiss* determined the number of stomata on the epidermis of 

 Vioth surfaces of 167 leaves of plants ; some of his results are given 

 below ; 



In one square millimelre. 



Upper side. Under side. Upper side. Under side. 



In one square inch. 



Olea Europea 



Vinca minor . , 



Juglans nigra 



Ailanthus gland ulosa 



Syringa vulgaris 



Helianthus annuus 



IBrassica oleracea 



Platan us occidentalis 



Populus dilatata 



Solanum dulcamara 



Euphorbia cyparissias 



Madura aurantiaca 



Betula alba 



Berberis vulgaris 



Pisum sativum 



IBuxus sempervirens 



JPrunus Mahaleb 



Asclepias incarnata , 



Datura stramonium 



Taxus baccata 



./ea mais 



Chenopodium ambrosioides. . 



Ticus elastica 



Eibes aureum 



'Populus monilifera 



IPinus sylvestris 



Anemone nemorosa 



Xilium bulbiferum 



Iris Germauica 



Avena sativa 





 

 

 

 



175 



138 

 

 55 

 60 

 

 

 

 



101 











67 



114 

 



ist 











89 



50 











65 



48 



625 



477 



461 



386 



330 



335 



303 



278 



270 



263 



259 



251 



337 



229 



216 



208 



204 



191 



189 



166 



158 



156 



145 



145 



131 

 71 

 67 

 63. 

 58 

 37 























112,875 



88,910 







35,475 



38,700 



















65,145 











43,215 



73,530 







60,630 



118,680 











57,405 



32,350 











41.925 



30,960 



403,125 



308,665 



398,345 



248,970 



312,850 



309,625 



194,790 



179,310 



174,150 



169,635 



167,055 



161,895 



152,865 



147.705 



139,320 



134,160 



131,580 



123,195 



121,905 



107,070 



101,910 



100,620 



93,525 



93,525 



84,495 



45,895 



43,315 



39,990 



38,410 



17,415 



*In a paper on the Number and Size of Stomata, published \r\ 

 Prin^sheim'a " Jahrbiicher fiir Wissensohaftliche Botanik," 1865. 



