This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 edition. Excerpt: ... In particular, plant 2 of Series IV was one of the largest Ceratophyllum plants I have ever seen. Yet, as has been seen in all our material, 30 whorls is the maximum for primarybranch length. We must conclude, then, I think, that under natural conditions the mean leaf-number per whorl becomes ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 edition. Excerpt: ... In particular, plant 2 of Series IV was one of the largest Ceratophyllum plants I have ever seen. Yet, as has been seen in all our material, 30 whorls is the maximum for primarybranch length. We must conclude, then, I think, that under natural conditions the mean leaf-number per whorl becomes practically constant after the formation of from 15 to 20 whorls. This number is 10. To reach a mean leaf-number of 11 the branches must have more than 175 whorls, while to raise the mean to 12 would require the occurrence of primary branches with more than 900 whorls each! Such an occurrence is of course far out of the bounds of reasonable expectation. Table 36.--Observed and calculated mean leaf-number in successive whorls on primary branches. Series IV. Another matter which demands consideration is this: We have reached our generalized law of growth from a study of plants collected at one place, namely, Carp Lake. Do plants from other localities follow the same law of growth? I think it is evident on general grounds that this is altogether likely to be the case, and table 34 and fig. 11 show very clearly that it is so. The law of the change in mean leaf-number with successive whorl formation must be the same to lead to such parallel results as we find on comparing any two series, as for example, Series I with Series IV or Series VI, etc. I propose to show in another way, however, that the law of growth which we have deduced is general for Ceratophyllum. A glance at fig. 11 indicates that the most marked difference between Series IV and Series I, II, or III in respect to the regression of leaf-number on position is that for corresponding positions the mean leaf-number is in general higher in Series IV than in the other three series. Now, suppose...
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