$2 The Mycetozoa, and 



injuring the young spores (as in Badhamia, Fig. 2). This 

 wealth of plan, this variety of scheme for effecting the 

 same end, and with the same or nearly the same materials, 

 is not unfrequently found in the works of Nature. One 

 might suppose, if Nature were striving to do the one thing 

 needful with the utmost economy, and in the very best 

 way, that there would be one, and only one way which was 

 the cheapest and best, and that this would, on the principle 

 of the survival of the fittest, be found everywhere to pre- 

 vail. But this is by no means always the case. Look at 

 the vast variety of schemes, by which, in orchids, insects 

 are made to solve the problem of getting the pollen-masses 

 out of the boxes into which they have been stowed away, 

 and then of pollinating with them the stigmatic surface. 

 Or look again at the vast variety of the forms of the peri- 

 stomes in mosses (all varieties of the same elements and 

 of the same fundamental idea), and the various ways in 

 which they operate under the action of moisture. Or take 

 again the insectivorous plants. Here the problem which 

 Nature seems to have set herself is this given a leaf, how 

 to catch insects ? And this problem has been solved by 

 the use of different constituent parts of a leaf in almost as 

 many ways as there are genera of insectivorous plants. 

 Or, once more, take the case of birds fitted for subaqueous 

 locomotion. Here the problem seems to have been given 

 wings and legs, how to drive the body through the water ? 

 and this has been solved, as we know, sometimes by using 

 the wings, sometimes the feet, as paddles, and with a 

 wealth of variation that is very remarkable. In all these 



