xv] SOME CONCLUDING REFLEXIONS 131 



All through their lives spiders seem to be gifted 

 in a high degree with the power of extracting the 

 utmost value, in substance and in energy, from their 

 food. Consider the great Theraphosid spiders the 

 so called bird-eaters. They have a massive body, 

 and great muscular power to sustain ; yet they are 

 never heavy feeders and can go for many months 

 without any food at all. And it is not as though they 

 were dormant during this period of abstention ; their 

 vital processes seem to be going on as usual the 

 whole time, and they are ready at any moment to 

 resent attack, or to employ their spinning organs 

 during their long fast. True hibernation, as we have 

 seen, does not occur in this group ; if it did, there 

 would be nothing remarkable in the occasional long 

 abstention from food. The vitality of a hibernating 

 animal is practically at a standstill ; all its vital 

 operations breathing, blood-circulation, muscular 

 action are reduced to the lowest possible limit, and 

 it very likely expends no more energy during its 

 winter sleep than it would during a day or two of 

 active summer life. 



But of such reflexions there is no end, and many 

 such will doubtless arise spontaneously in the mind 

 of the thoughtful reader, and it is for that very 

 reason that the study of the life-history of any animal 

 is of such absorbing interest. It is not contended 

 that spiders are any more wonderful than any other 



