April, 1903. ^9 



WHAT IS AN ANNUAIv? 



BY R. LIvOYD PRAEGKR, B.A., M.R.I. A. 



I BKiviEVK I am right in saying that the common conception of 

 an annual plant is one which rises from the seed in spring, 

 flowers and fruits during the summer and autumn, and dies 

 as winter advances. This conception is, no doubt, confirmed 

 by the observed behaviour of many of our favourite garden 

 flowers ; Sweet Pea, Mignonette, or Nemoph3dla we sow in or 

 out of doors in the spring montlis, they brighten our gardens 

 during the summer, and we consign to the rubbish heap their 

 dead or dying remains before winter has settled down on 

 us. They thus run through their life-cycle within the calendar 

 year. 



But does the calendar j^ear mark the limits of the life of 

 annuals in a state of nature ? A little observation will convince 

 the botanist that, in our Irish climate at least, it often does 

 not. 



Turning to botanical glossaries, we find some am- 

 biguity in their definitions. Thus lyamarck says^ 

 " Annuei,i,e, . . . parmi les plantes herbacees, celles qui 

 perissent entierement dans I'annee meme de leur naissance." 

 lyindley remarks^ ''Annuai,. — Flowering and fruiting in the 

 same year in which it is raised from seed." Babington says^ 

 '^ Annuai. plants rise from the seed, flower, and die in the 

 same year." While in the latest glossar}', Daj^don Jackson 

 writes^ " Annuai,, . . . within one year; used of plants 

 which perish within that period." It is not clear in any of 

 these quotations whether the calendar year, or a period of 

 twelve months, is intended — apparently the former, in some 

 cases at least. 



A more correct definition of an annual would appear to be 

 — A plant which completes its life-cycle within twelve ni07iths. 



1 Eiicyclopedie Metliodique. Botanique. Tome I. 1783. 

 * A Glossary of technical terms used in Botany. 1S48. 

 ' ^lanual of British Botany. 

 ' A Glossary of Botanic Terms 1900. 



