REPRODUCTION IN PLANTS 



CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 195 



John M. Coulter 



In connection with the vast accumulation of facts concerning 

 reproduction, our morphological categories are in danger of becom- 

 ing too rigid. Emphasis is laid upon secondary features, and the 

 fundamental features common to all reproduction escape attention. 

 An extensive terminology further enforces rigidity of classification, 

 because terminology makes exact definitions necessary. As a 

 consequence, the various so-called "types" of asexual and sexual 

 reproduction are pigeon-holed in our texts as though they had 

 nothing in common. It is the purpose of the present paper to 

 attempt a tentative analysis of the phenomena of reproduction as 

 observed in plants, to eliminate the secondary features that make 

 for too great rigidity of conception, and to discover the facts which 

 are common to all reproduction, which underlie all superficial 

 differences, and which, therefore, relate naturally the various 



•■ 4-, 99 



types. It is hoped that such an analysis may serve, not only to 

 soften morphological distinctions, but also to suggest research that 

 will deal with fundamentals more than with superficial details. 

 In such a presentation it would be impossible and confusing to pay 

 attention to all of the variations recorded. Only the general situ- 

 ations can be included, so that the conclusions reached will not 

 seem to satisfy every case, but the point of view will be indicated 

 which can eventually adjust all details. 



The use of the term " reproduction" in this paper must be 

 defined. Any cell that produces another one is performing the 

 function of reproduction, but the result may be merely the growth 

 of an individual, the restoration of wasted tissue, or the healing 

 of a wound. Reproduction will be used as meaning the production 

 of new and independent individuals, which is the current under- 

 standing of the word. 



337] 



[Botanical Gazette, vol. 58 



