Instinct and its Lessons 107 



down, in form of habit, does not in the least impair 

 the necessity of a basis wherefrom the first impulse 

 might start. Archimedes might have moved the world 

 could he but have found a fulcrum, and Nature's 

 machinery, however complex it be, and however remote 

 its ramifications, must, no less than his, depend for its 

 power of doing work upon the basis, whereby it is 

 upheld. Once get habit solidly mounted and no doubt 

 it may transmit its forces, but being habit it cannot be 

 its own foundation. 



Thus much premised, let us explore the narrower 

 territory in which Darwinism claims to reign. And 

 first we have to inquire whether it be a tenable hypo- 

 thesis that the instinctive habits, which we witness 

 amongst the brutes, had their origin in what we describe 

 as fortuitous acts. On this question there is no need to 

 dwell at length. Darwinians assert that this hypothesis 

 is conceivable. Let us take a few instances, and ask 

 ourselves to conceive it. 



Without again recounting the story of the Sphex we 

 may refer to it once more in this connection. The 

 instinct here manifested is by no means without a 

 parallel, it is not even the most wonderful of its kind. 

 Another species of the same genus uses Caterpillars 

 instead of Crickets, and to paralyze them from six to 

 nine stings are needed, one between each of the 

 segments of the body, the brain being also partially 

 crushed by a bite with the mandibles. Another species 

 of Wasp, Tachytes, uses Grasshoppers in a similar 

 fashion, and to reach the desired nerve has to bend 

 forward the victim's head and bite through a membrane, 

 but if Grasshoppers fail it will take a Caterpillar. The 

 Ampulex prefers Cockroaches, but will make a shift with 

 other insects: the Stethorectus chooses Spiders by pre- 

 ference, even the huge Bird-spider which devours Hum- 

 ming-birds, but can do with Grasshoppers and Cater- 

 pillars. An instinct fundamentally the same is occasion- 

 ally found in animals altogether different. Thus there 

 have been found in a Polecat's nest as many as forty 



