2 5 2 The Botanical Gazette. [September. 



period, and of every organ, must eventually be taken into ac- 

 count before the last word can be spoken concerning a Nat- 

 ural System. The possibilities of adaptation seem so great that 

 it is possible to conceive of two forms closely related in fact, 

 but widely separated by some schema which depends upon 

 any one set of organs however dominant. For example, this 

 trouble has been experienced over and over again in all pre- 

 sentations of Thallophytes, and will probably continue to be 

 experienced so long as some single key is used to unlock all 

 the mysteries of affinity. I cannot see why a single set of 

 characters used by an embryologist may not result in as arti- 

 ficial a scheme as the use of two or three organs by the tax- 

 onomist. 



I have thus spoken of the study of life-histories to indicate 

 that its chief function lies in the field of Systematic Botany; 

 to suggest that it take into account development at every 

 period and of every organ, and so obtain a mass of cumulative 

 evidence for safe generalization; and to urge upon those not 

 thoroughly equipped great caution in publication. 



I fear that what has been said concerning the great difficulty 

 of the work of the two phases of Systematic Botany al- 

 ready mentioned may be taken to imply that there is nothing 

 here for the poorly equipped but well-intentioned to do. My 

 frank opinion is that there is an abundance of service that 

 such can render, and that their chief function is to bring 

 facts to the notice of those who know how to use them. 

 Very few of us can be architects, but almost any one can 

 carry brick and mortar. 



HI. The coxsTRtJCTioNM)F a Natural System.— This 



ts, of necessity, the last phase of Systematic Botany, and it is 

 evident that its work will not be complete until the two pre- 

 vious kinds of work have been exhausted. The fact is, it must 

 lay under tribute every department of botanical work, and be 

 a compendious expression of man's knowledge of the affinities 

 ot plants. It lS just here that the work of the tyro is most 

 common and least harmful ; for crude systems need not annoy, 

 they can be buried and no law requires their embalming, no 

 neccss.ty compels a verification of their facts, for no facts are 



t'ion H^ e r T* ^ arC aIrCHd y known " I venture the asser- 

 ,m1,oV CU K> aniStS Can truthfuI1 >' deny that in the early 

 had n !■ r bltlOUS Sta ? C ° f thL ' ir development they either 

 had m mind, or were rash enough to publish some idea that 



