OF WASHINGTON. 199 



the snow border. In a region where the highest plants do not 

 reach over six inches, as at Ft. Conger, (Lady Franklin Bay 

 Expedition), Hospital Steward Biederbeck observed large-sized 

 spiders which looked like the Kreuzspinne {Epeira diademata) 

 of Germany having made webs between the Saxifragas from 

 four to six inches high . (This was probably E. patagiata . ) Now 

 these orbweavers never constructed their webs so close to the 

 ground under ordinary circumstances. 



These two points prove therefore, from actual observation, that 

 the spiders are capable of accommodating their habits to the 

 surrounding conditions. 



The curriculum of plant and lower animal life is limited in 

 these northern regions to the few weeks of arctic summer, and 

 what takes generally weeks to develop under other conditions 

 is here accomplished in days, for the time is short a whole 

 life has to be lived through in this short space of time and 

 nature is now in busy haste. 



The polar spider leaves its egg-shell at the first sign of the 

 thawing, and crawls out of its cocoon at the first warm ray 

 of the sun. Its development is so rapid that the collector 

 rarely catches an immature form. It finds ample food in the 

 swarming Diptera, Neuroptera or Lepidoptera and it has 

 attended to all its material duties before the parting sun-rays 

 have ceased to spend their warmth upon the freezing earth. 



These duties consist principally in preparing the eggs for the 

 perilous stage of hibernation. If we look upon the ways in 

 which the spider under more favorable conditions preserves its 

 eggs, we find two principal methods : First the cluster of 

 eggs, generally many in number, the inner ones protected by 

 those on the outside, and always surrounded by a bundle of 

 silken threads, the product of the spinning organs ; this cocoon 

 is covered by a strong, paper-like, and waterproof sheath and 

 then fastened in a recess on the underside of a stone which is 

 half sunk into the ground, as in the Drassidae. Thus the 

 dormant life of the embryo is protected from the perils of 

 external influences, for buried under the ground it is secure 

 from rain and frost by means of a non-conductive fabric of 

 sufficient thickness, for we may well presume that these layers 

 are in those regions made much thicker than with the same 

 species in a warmer climate. 



The other method by which the spider hibernates is the 

 following : Many forms spin around the egg-mass a quantity 

 of loose threads without the waterproof paper-like covering, 

 but these are none the less securely protected by the fact that 

 they are spun on the leaf of a plant, and the leaf is wrapped 

 around the cocoon and its edges securely fastened by glue or 

 threads so as to make the whole also waterproof. Although 



