Teachers' Leaflet. 575 



LESSON CXXXIX. 

 the dandelion blossom. 



Purpose. — To give the pupils an understanding of the structure of 

 the dandelion flower. 



This being one of the composite flowers difficult to understand, the 

 children should be taught to regard each blossom as a large family of 

 flowers living together. (See Lessons XXXVI to XL, this series.) 

 Note that in the case of the dandelion each little flower has a banner of 

 yellow, and each flower is perfect and will produce a seed. Let the 

 pupils count how many flowers there are in one family ; this number 

 ranges from one hundred and fifty to two hundred usually. Let them 

 note the following things about the flower head : How it looks in the 

 bud ; how many of the flowers are in blossom the first day ; the second 

 day, etc., covering its history until the blossoms fade ; note that it looks 

 like a bud again while the seeds are ripening ; note that the blossom 

 heads close on dark days and nights ; notice all of the kinds of insects 

 found working on the dandelion, and that these are the pollen carriers. 



LESSON CXL. 



THE STRUCTURE OF THE DANDELION SEED. 



Purpose. — To call special attention to the dandelion seed. 



Take several blossom heads which have closed after blossoming but 

 before they have opened as seed heads. Tear one apart and note how 

 the balloons are developing from the blossoms; while it is thus shut up 

 the little stems that hold the seed to the balloon are elongating. Study 

 the opening of the seed head and how long it takes to make a perfect 

 globe. Note that this globe is made by the bending back of the bracts 

 which enfolded the flower and the seed head, and note the different 

 angles of the seeds to the base on which they are fastened. Pull oft' a 

 single seed and if possible study it with a lens. Note the difference 

 between this and the thistle or a milkweed seed, so that the pupils will 

 understand that the dandelion seed is never at the center of the balloon. 

 Take off the seeds one by one and notice the little pit where each seed 

 was borne ; count the seeds and then give an arithmetic lesson. Estimate 

 how much ground is occupied by a vigorous dandelion plant; this would 

 be at least five inches square and might be more. Let them multiply 

 this by the number of seeds in a head, then go out in the yard and 

 measure off the amount of ground that the seeds of one head would 

 cover if they should all gain foothold and gro,w- 



