38 A HALF-HOUR WITH THE 



expanded membrane, on which grow the true repre- 

 sentatives of the ovules, which, coming in contact 

 with the microscopic spores, develop new plants. 



Another family of these flowerless plants, which 

 have yielded highly interesting results to the mi- 

 croscopic observer, is the horsetail. If these are 

 gathered in the spring of the year, they will 

 present two forms ; one showing the leaves and 

 green parts of the fruit ; the other, the leaves 

 changed into reproductive organs. These may be 

 very easily examined as opaque objects under the 

 Microscope. The spores are seated on round 

 shield-like disks (Fig. 114, a, PI 4). "When the 

 spores are examined by a higher power, they 

 present four spiral filaments, which are twisted 

 round the body of the spore (b). If the spore is 

 breathed upon whilst under the Microscope, the 

 spiral filaments gradually relax their grasp, and 

 they become expanded and attached to the spore 

 only at one end (Fig. 114, c, PI. 4). 



The study of the flowerless plants is one of 

 never-ceasing interest. Within the last few years 

 much has been done by the aid of the Microscope 

 to clear away the mystery which surrounded the 

 functions performed by certain organs they pos- 

 sess. Much more, however, remains to be done ; 

 and an interesting field is still open to the inquiries 

 of the microscopist. We will now, however, take 

 our Microscope to the pond- side, where we shall 

 still find many plants to interest us, belonging to 

 the lower, or flowerless groups, together with ani- 

 mals, the companions of their aquatic life, and the 

 representatives of their simpler mode of existence. 



