Home Nature-Study Course. 367 



19. Study a bur of a burdock and find how many seeds each bur 

 contams and how they are situated. Sketch one of the hooks of the 

 bur. 



20. The blossom of a burdock and of a thistle are not unhke in 

 general appearance. Explain the difference between the utility to 

 the plant of the spines on the burdock and those on a thistle blos- 

 som. Study the stick-tight or a pitch-fork and notice where the 

 seed is and where the hook is, and describe how the burdock differs 

 in these respects. 



21. In this connection, the teacher has a good opportunity to 

 determine for herself that appearances often are deceitful. Thistle 

 seeds travel by balloons; but do all kinds of thistles spread them- 

 selves freely by this means? Make a careful study of the Canada 

 thistle. How many good or fertile seeds do you really find in each 

 head? How else does the Canada thistle spread itself? Why are 

 Canada thistles foimd in patches and the bull thistle not? 



'j; 22. The burdock and many others were introduced to America 

 from Europe. Write a short imaginative story of how the first 

 burdock seeds were brought across the Atlantic. 



23. How would you teach seed germination in connection with 

 seed distribution? 



Correlation of Seed Distribution with Geography Work and 



Language Work. 



Perhaps no one subject in Nature-Study touches geography at so 

 many points as does that of seed distribution. 



In a way, every seed that floats is a voyager and a geographer, 

 for if the geography does not afford the seed a fitting environment 

 it cannot grow. If a " thistle-blow" falls in a pond or is driven into 

 dark woods, it will not produce a plant, for it must have dry soil 

 and simhght in order to develop. The reason why wild carrot 

 grows by our roadsides and in meadows and not elsewhere; and the 

 reason why daisies grow on our upland meadows and pastures and 

 roadsides^ and why the Canada thistle grows in a meadow, are all 

 questions of geography. That the water lily seeds are distributed 

 by water and that the plane tree grows mostly by streams, and almost 

 every other fact of plant life, is a matter of geography. 



Many of our weeds are introduced from Europe and it is a profitable 

 line of speculation for the children to imagine how these emigrants 

 stole their passage across the Atlantic. To think of these things 

 specifically will help develop a geography imagination, which is 

 absolutely necessary for a comprehension of geographical ideas. 



