168 NATURE-STUDY REVIEW [7:7— Oct., 1911 



The work of identification proved intensely interesting. In 

 many cases the plant and seed were both necessary. The pupils 

 brought both to the c!ass room. Here they had at their dis- 

 posal, The Second Ohio Weed Manual, a Bulletin on the Seeds 

 of Michigan Weeds, and a tripod-lens. After identifying a speci- 

 men the seeds were placed in small vials and labeled. At first 

 we went to the school garden for our weed study. These trips 

 soon became unnecessary as the boys brought in weeds which they 

 wanted to identify. Usually some member of the class thought 

 he knew the weed. He attempted to prove its identification. 

 Sometimes he failed to satisfy the pupils ; and then the matter 

 was fully investigated. In such cases the on!y thing to do was 

 to study the seed and commence a search in the Michigan Seed 

 Manual. 1 In this Manual seeds of natural size and magnified 

 seeds were shown. In case the seeds were small the lens was used 

 in order that its peculiarities might be noted. The lens proved 

 useful in detecting the white spots on the catnip seed ; and al- 

 most necessary in studying the waxball seed, with its irregular 

 vertical lines and the black spots. The steel weed presented a 

 new prob 1 em. No one could suggest a name and the seed was 

 not to be found in the Michigan Seed Manual. It was only after 

 consulting the weed herbarium of the Agricultural Department 

 that the weed was identified. Crab grass, small crab grass, and 

 finger grass were also distinguished by means of the herbarium. 

 Yet most of the weeds were identified by means of the manuals 

 mentioned above, and the lens. In identifying the weeds many 

 interesting things happened. One day the entire class agreed 

 that a certain specimen was the horse weed. They consulted 

 their manuals to make sure. Those referring to the Michigan 

 manual found the horse weed seed to be oblong, cream in color, 

 1 to 1.3 mm. long. Our seed certainly did not correspond to this 

 description. Those with the Ohio Weed Manual at hand found 

 two weeds, the horse weed and the ta 1 l ragweed, sometimes 

 called the horse weed. The former had very narrow leaves, un- 

 like the leaves of our specimen. The tall ragweed or horse weed 

 had leaves like those of the plant under consideration and up- 

 on looking for tall ragweed in the Michigan Manual the seeds 

 were found to correspond. The seed was found to be very much 

 like those of the ordinary ragweed in shape. Thus it was con- 

 cluded that the plant was only locally known as the horse weed. 

 Thirty-two common weeds were soon identified by the class. 

 Not only were the pupils familiar with the plants but also with 



1 See List of References Useful for Study of Weeds page 175. 



