34: LABOEATOnV sTi'DlES (JF THE HOOT 



summary could come ouly after a guoil deal of lookiug into particular cases 

 Observatious sliouM be uuuibered ii*. the notebooks; and siieciiueu parts <tl 

 tlie plants whose buds are described should he kept pi'operiy luunbered, for 

 deleruiiuing with certainty what the plants are that have been studied. There 

 are several popular works from which the names of plants in flower, or of trees 

 even not in flower, maj' be made out to some extent, ff one learns the use 

 oi the JIanital, names may be determined without other help. Assistance 

 may often he had from a trained botanist through correspondence, if none is 

 a\ailable near at hand. 



I. Summer. Growing liuds. Protection of the tenrler tips : against (") iii- 

 x«i:tx, {b) xnails (water plants ami low mider-herbs), (c) mn/ olher aniiiuih .' 

 ((?) excessive light, hrot. and ilri/i/ii/ ; by means of (o) slipule.f, {h) pptiolpx 

 of older leaves, (c) tri'.-Jtniur.^. (d) convergence and ouersJiaJiug by all the 

 parts generally, (e) other ornoigpinentx. 



If. Summer, fall, and winter. Resting (or "winter") buds. A. When 

 are they formed, in diiTerent pl.inls ? B. Sources of danger. Determine some 

 of these by actual observations on {k) bints — c.,'/. note llic food of flocks of 

 northern birds that visit your localily in winter — and CO other onimols. 

 As to temi)erature, it nia\" l)e asked. />" hnit,-: n-rr-je .^ Jn>rs f'rei r^ing kitt .^ 

 Does f,r,.tongeit frrrzing l;itt.> ln,rs tlifijring kit! .' ('. M.-tliods of offsetting 

 tlie <langi.'rs by (") sp-rint ■irotes (\\-]i;il is the nature, or miu'pbnlogy, of the 

 scales'.'), {ti) cr/Z/z/i/.s' (.r the jiarls (wik.I, -landular secrclinns), (c) seelifsio/i 

 (1) under h.ark. (L'l in luilluws. (J) oilier means. 



III. Kxperiinriii al. Karl if 'si rliite a I which Imds of di I fr rent species can be 



made lo open, wiiliin doors. ]-]rrf<-ts of removing soi r all hF the scales in 



certain species. Do buds grow at .all, in diameter nv length, bet^\"ccn Decem- 

 ber 1 and JIarch ], or otherwise i.-hange? 



V. LABORATORY STUDIES OF THE ROOT 

 E.XEHci.sE XIV. Tup: GKXi;i;-\L 3IoRrn()L(i(,Y (jf tiii; 1!oot 



The root suggested is that of Shepherd's Purse. (Do not remove 

 the leaves from the plants.) 



Note the general habit of tlie root system, consi,sting of one main 

 root Qaproot), and numerous lateral roots and rootlets. 



What is tlie direction of growtli of the taprnot V Of tlie lateral 

 roolsV Examine the t;n>root willi tlie lens for contraction wrinkles. 

 Vi what service is contraction of tlie j-oots, in the case of siidi a plant? 



Place some of the fine, filwoiis rootlets on the stage of the dissecting 

 microscope in watei', and carefully pick apart with needles, so as to see 

 tlieir length, branching, and relative slenderiiess. Can root hairs be 

 made out? Does the branching show regularity? Is the root iointed 

 where branches .spring out? ,\t what angle do tlie branches spring? 



Chip away one side of the main root to show the wood at tlie center. 

 (In doing this, sa^e half or more of tlie iipjier' ]iart iincut. for later 

 use.) This i,-. the ,;ciii ral c///;„,/,r. All out>idi- i.f Ihi^ i, Ihe mrtrr 

 (bark). Hy scraping and si rip].iiig, a dislinci cxlconal laver. like a 

 skin, may lie delached from tlie taproot. This i-esembles the external 



