DARWINISM ATTACKED. 81 



Copepods floating in the pelagic waters of the Aleutian seas, 

 what Copepods shall disappear forever? Mainly, we may 

 say, the chance of position. A bit more or less of size, or 

 strength, or redness, or yellowness, or irritability or what 

 not of form and function is going to avail little when the 

 water rushes into the yawning throat. Now this chance 

 and this luck are the luck and chance of the law of prob- 

 abilities ; that is, luck and chance capable of being mathe- 

 matically determined. Given so much ocean, w r ith so many 

 .whales swimming about in such and such curves at such and 

 such rates and opening and closing their mouths inter- 

 mittently at such and such intervals, and just so many 

 shoals of so many million Copepods, these shoals at such and 

 such distances apart, and any mathematical friend will 

 reckon for you the chances any one Copepod individual has 

 at any given moment of being swallowed. But Darwinian 

 variations in the Copepod body will be represented by no 

 function in the mathematician's formula. When the scores 

 of little streams dry in California every summer, what deter- 

 mines whether millions of Californian water-insects of 

 scores of kinds shall die in July or not? Mainly life or 

 death is determined for them by their good or ill luck in 

 being in one of the few streams that do not dry up, or in 

 one of the many that do dry. Kelsey Creek runs into 

 Clear Lake, in northern California ; it is usually ever-living, 

 but some summers it suddenly dries up. Fish play back and 

 forth between this stream and the lake; at the time of the 

 sudden drying a few hundreds of thousands out of many 

 hundreds of thousands that habitually live in the stream and 

 adjacent lake waters find themselves one awful day gasping 

 painfully for water to wet their drying gills. They gasp a 

 short while and then die. Did they all have the same num- 

 ber of scales, the same shape and size of body, the same 

 tinges of fleeting colour ? No, they represented most of the 

 possible gamut of Darwinian variation for their particular 



