198 KANSAS ACADEMY OF SCIENCE. 



DISSEMINATION AND GERMINATION OF SEEDS. 



By Wesley N, Speckmann, Kansas Wesleyan University, Salina. 

 Read (by title) before the Academy, at Topeka, December 31, 1904. 



/"\NE of the most important subjects in the study of botany, as well 

 ^^ as one of extraordinary interest, is that of the dispersal and ger- 

 mination of seeds. It is one that has received the attention of inter- 

 ested students for ages, and one of which a passing notice will not 

 suffice. If we take, for example, a common morning-glory {Ipomcea 

 purpurea Lam.), which is only a moderately prolific plant, and which 

 is said to have some 3000 seeds in a single season, we will find that in 

 seven years, at this rate, the enormous number of 729,000,000,000,000,- 

 000,000,000 seeds will be produced. If nature intended that each of 

 these seeds should germinate and develop into a plant, there would 

 need be some wonderful means of dissemination of the seeds over a 

 wide range of territory, which would soon comprise the entire surface 

 of the globe. It is, therefore, clear that the manner in which seeds 

 are distributed is one of vital importance to the maintenance of plant 

 life upon the earth. 



An omniscient creator has provided various devices for transport- 

 ing seeds ; not only is this true of dehiscent but of indehiscent fruits 

 as well. 



The important means of transportation comprise the following: 

 (a) Wind, (J) water, (c) man, {d) lower animals, and (e) hygro- 

 scopism. 



The dispersion of seeds by means of winds is an interesting sub- 

 ject. In cases of this kind the seed or fruit is light and buoyant, as 

 in the dandelion ( Taraxacum officinale Linn.) When the akene of 

 this plant matures "the beak lengthens and elevates the pappus; then 

 the involucre is reflexed, the pappus spreads and, with the fruit, is 

 blown away by the wind," ^ closely resembling a parachute, except 

 that it rises instead of descending. 



Another example is that of the sow-thistle {Sonchus asper Vill.), 

 which has a pappus of delicate downy hairs. In the virgin's bower 

 {Clematis It.) the akene retains the feathered style, which aids in 

 dissemination; so, also, in the milkweed. 



Among the many other examples of dispersion of seeds found in 

 the family of Compositse, suffice it to mention further the common 

 thistle {Cnicus lanceolaius Hoffm.) and the Canada thistle {C. ar- 

 vensis Hoffm.), the latter being the plant that makes life miserable 



1. Gray's School and Field Book of Botany. 



