144 



HUTCHINSON'S POPULAR BOTANY 



living fire. " Large animals have been noticed standing among its crushed 

 and broken tendrils, dripping with the gleaming fluid, and surrounded by 



a seeming network of fire." 



Passing now from the Flower- 

 ing Plants, we come to the non- 

 flowering or Cryptogamic, to which 

 the Mosses, Seaweeds, Fungi, etc., 

 belong. Here we meet with some 

 very striking and unmistakable 

 instances of luminosity, though in 

 some of these, doubtless, the phe- 

 nomenon is connected rather with 

 the process of assimilation or 

 decomposition than with electrical 

 conditions of the atmosphere. We 

 have seen that assimilation com- 

 mences with the decomposition of 

 carbon dioxide in the chlorophyll 

 corpuscles, and that this takes place 

 under the action of light. Light 

 is therefore absolutely essential to 

 the successful discharge of the 

 functions which are carried on in 

 green tissues ; and hence the very 

 interesting adaptations for increas- 

 ing light intensity in plants which 

 grow in caverns and grottoes and 

 in the twilight depths of the sea. 

 Certain caves of Central Europe 

 have long been celebrated for their 

 luminous Mosses. On entering one 

 of these caves, the eye is at once 

 attracted to the floor of the cham- 

 ber, which gleams and sparkles 

 with minute points of golden-green 

 light. The ignorant beholder might 

 imagine that he had stumbled upon 

 a store of hidden emeralds, but 

 any hopes of sudden enrichment 

 fostered by such a thought will be 

 quickly dissipated ; for the treasure 



FIG. 181. RHIZOMOKPH. is only gnome's treasure at best. 



On bringing the supposed prize to 

 the light, it is found to consist 



Photo by} 



[E. Step. 



Strands of mycelia of the Honey-coloured Mushroom (Ar- 



millaria mellea), which has often been observed to give out 



light. 



