HARSHBERGER— STUDY OF THE CLOVERS. 137 



were found in the pods of each species, which were sent in the un- 

 cleaned condition. The samples of Trifolium repens showed from 

 1-4 seeds in each legume. Trifolium elegans and T. montanum had 

 1-3 seeds. Trifolium resupinatum, T. ruhens, and T. suffocatum 

 yielded 1-2 seeds. The following species, arranged alphabetically, 

 had only one seed in each pod, and this held good for these species 

 from different countries : agrarium, alexandrinum, alpestre, angusti- 

 folium, arvense, hadium, bocconi, dubium, elegans, incarnatum, john- 

 stoni, leucanthum, maritimum, medium, minus, montanum, nivale, 

 ochroleiicum., pannonicum,, pratense, procumbens, reclinatum, repens, 

 repens var. macrorhiza, resupinatum, rubens, scabrum, spadiceum, 

 squarrosum, stellatum., striatum,, suffocatum. 



Weight of Seeds. 



The weight of the seeds was determined in milligrams. Some of 

 the samples were sufficiently large to permit the weighing of one 

 hundred seeds of each. Others contained only a small number of 

 seeds, so that ten was the maximum number the weight of which 

 could be determined. In order that the results might be made com- 

 parable, the weights in each case are calculated on the ten basis. Of 

 course, the weighings were more accurate where the larger numbers 

 w^ere used. In some cases fifty seeds and in others twenty-five seeds 

 were weighed. In the accompanying list the weights determined by 

 weighing 100, 50, 25 seeds are placed in ordinary type. The weights 

 originally determined on the ten basis are printed in heavy-faced type. 

 The weights of the seeds of the various species of Trifolium are in 

 milligrams: agrarium (2, 5, 3.2, 5), alexandrinum (30, 31.5, 32.5, 

 34), alpestre (10, 12, 15.5), altissimum (17), angustifolium (12, 14), 

 arvense (2, 2.5, 4), aureum (3), balansce (5.4), bocconi (3, 5.5), 

 campestre (1.2), cernuum (2), dubium (3.3), elegans (4.5, 6.5, 7.5), 

 filiforme (4.5, 5, 5.5, 5.6), glomeratum (2.5, 3), hybridum (5,5, 5,5,5, 

 7, 7.5, 8,8) incarnatum (30, 32.3, 36, 36.5, 36.5, 37, 42.5), johnstoni 

 (5.3), lupinaster (17), maritimum (15, 17, 25), medium (12.5, 12.5, 

 13), minus (3.3, 5), montanum (5, 6.5, 7.5, 10, 11), nivale (5), 

 pannonicum (28, 33, 36.5, 37, 40, 41), patens (6.5), perreymondi 

 (3), pratense (13, 13.5, 14, 15, 15, 16, 16, 16.5, 17, 19.5, 20, 22, 25), 



