A Memorable Lesson 



zable substance that gives the luminous mush- 

 room its soft, white light, which is like the 

 beams of the full moon. It would be inter- 

 esting to know whether certain boletiturn blue 

 owing to the presence of an indigo which is 

 more liable to change than dyers' indigo and 

 whether the green of the so-called delicious 

 milk-mushroom when bruised is due to a like 

 cause. 



All these patient chemical investigations 

 would tempt me, if the rudimentary equipment 

 of my laboratory and especially the irrevo- 

 cable flight of age-worn hopes permitted it. 

 The day has passed for it now; there is no 

 time left to me. No matter : let us talk chem- 

 istry once more, for a little while; and, for 

 want of something better, let us revive old 

 memories. If the historian, now and again, 

 takes a small place in the story of his animals, 

 the reader will kindly excuse him : old age is 

 prone to these reminiscences, the bloom of 

 later days. 



I have received, in all, two lessons of a sci- 

 entific character in the course of my life: one 

 in anatomy and one in chemistry. I owe the 

 first to the learned naturalist Moquin-Tandon, 

 who, on our return from a botanizing expe- 

 dition to Monte Renoso, in Corsica, showed 

 42? 



