4 i 8 STUDIES IN SEEDS AND FRUITS 



scarcely claim. Since much of the substance of the two follow- 

 ing pages will be found in the text-books, it will be sufficient 

 to refer to the works consulted at the end of the chapter. 



Goebel points out that whilst with Ferns, Lycopods, and 

 Equisetums there is no rest-period, in Seed Plants with few 

 exceptions the embryo experiences sooner or later an interrup- 

 tion of its development which is resumed in germination. In 

 reality, though the pronounced exceptions are few, there are 

 many in degree, as is indicated by the transient nature of the 

 rest-period in a large number of plants and by the prevalence 

 of after-ripening, a term applied to the growth of the embryo 

 in the resting seed before and after detachment from the 

 parent plant. As regards the shortness of the period, let us 

 take our own forest trees. The seeds of the Oak, Beech, Elm, 

 Poplar, Horse-chestnut, Maple, Fir, etc., have, as is well 

 known, a very transient germinative capacity, as a rule only 

 preserving this power until the next spring, and even then 

 usually requiring to be planted soon after gathering. Probably 

 not a few of them, when their seeds germinate during a mild 

 autumn, supplement the short rest-period within the seed by a 

 period of repose outside the seed, remaining stationary during 

 the winter under the protection of the fallen leaves, and doing 

 little more than protrude their radicle an inch or two. This 

 capacity in the case of acorns is alluded to later on in this 

 chapter. 



Many other seeds are known to behave similarly. Thus, 

 those of Oxalis and Salix fail usually after a few weeks or 

 months. Professor Ewart strikes the true note when 

 he remarks that in very many cases seeds are very intolerant 

 of even ordinary air-drying. According to De Candolle, 

 the seeds of most Rubiaceae, Myrtaceae, and Lauraceae lose 

 their germinative capacity soon after detachment from the 

 mother plant. The seeds of the Palmaceae also often retain 

 this capacity but a few months. In reply to a letter, Mr Hart, 

 late Superintendent of the Botanic Gardens in Trinidad, tells 

 me that those of Oreodoxa, Sabal, Thrinax, Acrocomia^ Attalea, 



