ENTOMOLOGIST AND BOTANIST. 



219 



siMi-al, anrt found at ouo end. whore it was vent 

 .ml of tlie i-ell. that it was also an entin- fibre, 

 and I eould see that tlie wliite sjtots at the twili- 

 inu was not occasioned by a pore or a hole in 

 tlie wall of the cell. This observation was very 

 intefeslinu. because it gave me the opportunity 

 ofexiilainiiij-' such white spots at the ends of a 

 lender Hue in tlie eells of a moss (Sphagnum 

 _timbriaturii). which I was unable to do before 

 ■(Fig. 138). 



[Fig. 138 ] 



Sphagmun tirabri.atum. 

 This tender line is nothing else than a spiral. 

 This libre could not be isolated from the c-ellu- 

 lose, but it aiUiered very fast to it, and broke 

 just at the same place as the cellulose, as you can 

 iiiiiark in the lacerated cells of the edge of a 

 slice. "That might be considered as the tran- 

 sition to the poi'ous cells (ceUuldso' porosw), 

 in wMch the fibres are so growu together 

 as to appear like a continuous membrane beset 

 with little pores. Close by the fibrous cells 

 you can find them in the pith of Geranium (Fig. 

 137, c). It presented itself in the shape of a 

 ladder, the pores are horizontally disposed at 

 equal distances from each other; in the middle 

 of each pore you can see a transverse line divid- 

 ing it into two halves — an effect of interference 

 of light. In the tliickues-s of the wall of the cell 

 at Imth sides, and corresponding to the sjiace 

 between the pores, we remark a .swelling of the 

 i(llulo-.( . this i>, the result of the growing to- 

 gethu ot the fibre and ^\all 



[Fig IW ] 



Tran8\erse 



Libel cell-, of Cinchona calisaya. 



When the inside layers are deposited meiv 

 II the entire surface of the cellulose wall, ll 

 ,'e have a successive growing of the wall ii 



regular way, depositing ring upon ring, sjiiral 

 upon spiral, porous layer upon porous laxcr: or 

 the layers are deposited irregularly — the tirst is 

 mostly the case. 



A transverse and a longitudinal slice of lilici- 

 cells of the Peruvian bark (Cinchona ra/ixai/a) 

 givc> u> a splendid illir-ti-ation «f lliis. You 



another. (Fig. 13il.) 



1 In the starch-cells of the root of 



Sarsaiiarilla (Sini/aj- sarsapari/la) 

 tlif pores arc deposited with regu- 

 larity. I reiiiarki'd Dial, by culling 

 till' sli,-c. Ihc poivs near lli<' edoe 

 did not rend: and li\ addini; iodine. 

 the starch inside llic integer cell 

 (Fig. UO. b). attached with ils top 

 to the lower end of this liicerated cell, 

 took its blue color merely in accord- 

 ance with the law of Osmose. The 

 starch granules near the top (Fig. 

 UO.a). where Ihey are [Ki,M4i,: 



separated from the con- 

 tact of the iodine b.\' 

 two membranes 

 ored first and more 

 intensely, because the 

 capillarity sent a large ceirsaisaparuia. 

 iodine in that direction 





HOW TO STUDY THE (} 



The study of the grasses is attended with 

 some difficulty on account of the smallness of 

 the parts composing the flowers, and is under- 

 taken by very few, even of those who study 

 with some care the more conspicuous flowering 

 plants. But for those who will have the patience 

 to attempt their investigation. Nature spreads 

 out an open and inviting field, and the explorer 

 will be rewarded by discovciics of as great in- 

 terest as in any other deparlnicnl. 



Iiet us notice some of the principal parts, or 

 organs, entering into the flower structure of the 

 grasses. The flowers of grasses are sometimes 

 in spikes, as those of Timothy or Herd's-grass, 

 and sometimes in loose, open panicles, as those 

 of Red-top. Each spikelet, or smallest subdi- 

 vision of the spike or panicle, whether consisting 

 of a single flower or of a number of flowers, has 

 commonly a pair of outer husks called glumes. 



Each individual flower is composed of two 

 inner husks or scales called paleie, three stamens 

 (each consisting of a thread-like stem or fila- 

 ment), a pollen-box or anther, and a pistil, 

 composed of the germ and two hairy or feathery 



