40 PBACTICAL GUIDE TO GARDEN PLANTS 



The Pod or Legume, familiar in the Pea, Bean, Scarlet Eunner &c., 

 is a fruit splitting into two valves, bearing the seeds on the edges (see 

 Glossary, fig. 69). A Lomentum is a pod constricted between the seed 

 breaking transversely into distinct joints. 



A Samara or Key Fruit, like that of the Elm, Ash, or Maple, is an 

 indehiscent fruit furnished with wings (Glossary, fig. 97). 



A Follicle, as seen in the Pseony, Larkspur &c., is a simple carpel 

 opening on one side only (Glossary, fig. 57). 



The Capsule is a dehiscent fruit composed of more than one carpel 

 usually with many seeds (Glossary, figs. 26, 27). 



The Silique and Silicle are the long and short pods respectively 

 of the Crucifer order (p. 201) (Glossary, figs. 99, 100). 



The Cone is the peculiar multiple fruit of the Pine-tree family 

 (p. 972). The cones consist of flat scales overlapping each other, and 

 bearing the seeds at the base (Glossary, fig. 106). 



The Cremocarp is the name of the fruit of the Umbellifer family 

 (p. 464). It consists of two achenes which split apart when ripe 

 (Glossary, fig. 38). 



A Nut is a dry indehiscent fruit usually with one seed surrounded 

 by a bony wall, as the Hazel or Cobnut (p. 797). In the Oak, the nut 

 or acorn is fixed in a cup called the cupule, the whole fruit being called 

 a Glans (Glossary, fig. 61). 



INFLUENCE OF LIGHT ON VEGETATION 



All plants having green leaves or stems can only properly develop 

 and perform the function of assimilation or digestion by the aid of 

 sunlight. Mushrooms (see p. 1166) and other Fungi carry out their 

 functions with and without the aid of light. Some plants like as much 

 sunlight as possible ; others only a little, preferring a diffused light or 

 deep shade ; and others again seem to thrive better under intermediate 

 conditions, some leaning towards light rather than shade. 



Light is essential in any case to secure the formation of chlorophyll, 

 the name given to the green pigment found in the cells of leaves. But 

 this substance also requires a suitable temperature, and will not develop 

 in very cold weather. The absence of chlorophyll is noticeable by the 

 pale or yellowish appearance of the plants. 



Sometimes gardeners are not anxious that it should develop at all ; 

 hence the reason of blanching Celery (see p. 1130), Seakale (p. 1121) &c. 

 by covering the leaf-stalks over with soil, pots, boxes &c. The exclu- 

 sion of light prevents the formation of the green colouring matter, and 

 the stems are in consequence more palatable when eaten. 



