FRUITS AND FLOWERS H 



Of fleshy fruits present in winter, one of the most common 

 is the drupe (Fig. 21). This has the pericarp consisting of three 

 distinct layers, the exocarp, mesocarp, and endocarp, the endo- 

 carp taking the form of a hard stone surrounding the seed; fruits 

 of this type are often called "stone fruits". Examples are black 

 haw and hackberry. Drupes are usually considered as one-seeded, 

 but in some instances, as in holly, several stones (endocarps), 

 each with its own seed, may be surrounded by the same mesocarp. 

 The pome ( Fig. 22) is developed from a sever al-carpelled, several- 

 seeded inferior ovary, the fleshy portion being a combination of 

 pericarp and and roper ianth tube (a tube composed of the coalesced 

 lower portions of the sepals, petals, and stamens); examples are 

 hawthorn, chokeberry, and mountain-ash. The rose hip (Fig. 23) 

 is an aggregate fruit, having many separate carpels of a single 

 flower within the fleshy, hollowed -out receptacle. 



Dry fruits include the legume (e.g., redbud), a fruit with 

 one locule but splitting along two sutures (Fig, 24); the follicle 

 (e, g. , ninebark), like a legume but splitting along one suture only; 

 (Fig. 25); and the c apsule (e. g. , catalpa), a dry fruit of two or more 

 carpels, splitting into each locule (Fig, 26). AH these may be 

 classed as dehiscent (opening to permit the escape of numerous 

 seeds). Other dry fruits are indehi scent containing but one seed 

 and therefore not needing to open, since the entire fruit functions 

 as a single seed. Among dry indehiscent fruits are the achene, 

 a small fruit with the pericarp closely investing the seed (e. g. , 

 sycamore, with the many achenes compounded to form a globose 

 head); the s amara (Figs. 27, 28, 29), like an achene but provided 

 with a wing which favors wind dispersal (e. g, , elm, hoptree); and 

 the nut (Figs, 30, 31),like an achene but larger, with a hard lea- 

 thery or bony pericarp (e.g, , chestnut, beech). A special type of 

 a nut is the acorn of oaks, where the nut proper is borne in a cup 

 representing a modified involucre (Fig. 32). In walnut and hickory 

 the nut has some of the properties of a drupe, with an exocarp and 

 a mesocarp (the husk) separating from the hard bony endocarp (the 

 shell) ; such a fruit has been called a tryma (Fig. 33). 



FLOWERj . Very few woody plants produce their flowers dur- 

 ing the winter months. Witch-hazel, the only fall-blooming shrub 

 in our region, sometimes has its yellow flowers persisting until 

 winter (Fig. 38). Most winter-blooming plants, however, are in 

 reality pre-vernal (early spring) in nature, coming into bloom in 

 late February or March, and usually persisting into spring (or in 

 the event of unusually sustained cold weather, not beginning to 

 bloom until spring). Examples are willows, elms, and maples 

 (Figs. 34,35,36,37,39). 



GYMNOSPERM "FRUITS "-The seeds of conifers or cone-bear- 

 ing plants (pines, spruces, firs, etc) are borne exposed on the 



