128 Marvels of Pond-Life. 



CHAPTER XII. 



DECEMBER. 



Microscopic Hunting in Winter — Water-bears, or Tardigrada — Their 

 comical behaviour — Mode of viewing them — Singular gizzard 

 — A compressorium — Achromatic condenser — Mouth of the 

 Water-bear — Water-bears' exposure to heat — Soluble albumen — 

 Physiological and chemical reasons why they are not killed by 

 heating and drying — The Trachelius ovum — Mode of swimming — 

 Method of viewing — By dark-ground illumination — Curious diges- 

 tive tube with branches — Multiplication by division — Change of 

 form immediately following this process — Subsequent appearances. 



HERE is always satisfaction in finding a work 

 accomplished; but the attempt to delineate 

 some of the marvels of minute creation has 

 been a pleasant one, and we approach the completion of 

 our task of recording a Microscopic Year with some- 

 thing like regret. The dark, dirty December of the 

 great metropolis may not seem a promising time for 

 field excursions, but some ponds lie near enough to 

 practicable roads and paths to render an occasional dip 

 in them, not of ourselves, but of our bottles — an 

 easy and not unpleasant performance ; and if the 

 weather is unusually bad, we can fall back upon onr 

 preserves in bottles and tanks, which seldom fail to 

 afford something new, as we have been pretty sure to 

 bring home some undeveloped germs with our stock of 



