STRAWBERRIES 40 1 



velvety hair, and has a soft juicy mesocarp ; the nectarine, how- 

 ever, which is only a sport from the peach, has smooth-skinned 

 fruits. 



Ex. 204. — Examine the flowers of the plum, cherry, and sloe, cut longi- 

 tudinal sections of the flowers, and note the form of the receptacle and the 

 form and position of the various parts of the flowers, paying special attention 

 to the gynsecium. 



Ex. 20B. — Watch the development of the ovary of a plum flower, when the 

 latter begins to fade. What becomes of the receptacle ? 



Ex. 206. — Examine a half-grown plum or cherry. Observe the place where 

 the style was placed on the ovary, and also the position of the ventral 

 suture. 



Cut sections both longitudinal and transverse of the ovary every week from 

 the time the flower fades up to the time the fruit is ripe. Note especially the 

 growth in thickness of the parts of pericarp, viz., the endocarp or 'stone,' 

 and the mesocarp or ' flesh.' 



Ex. 207. — Measure the diameter of three or four fruits every week and 

 determine when the increase in the diameter is greatest. 



Ex. 208. — Make a collection of stones of the different varieties of plums and 

 cherries. In what ways do they differ from each other ? Compare the stones 

 of the peach, apricot, and nectarine. 



5. Genus Fragaria. Strawberries. — This genus comprises 

 three or four species of plants all with edible ' spurious fruits,' 

 of which the wild strawberry or any of the garden varieties may 

 be taken as an example. 



The calyx of the flower is garaosepalous of five sepals. Out- 

 side the calyx, and alternating with it, is a whorl of five sepal- 

 like members, constituting what is known as an epicalyx. Each 

 sepal-like member of the epicalyx represents two united stipules 

 belonging to the adjacent true sepals. 



A vertical section of the strawberry flower is given in Fig. 125. 



The receptacle is of peculiar form : it is a solid roundish or 

 cone-shaped structure, round the base of which extends a flat 

 rim. To the flattened rim is attached the corolla (b) of five 

 petals, and the androecium of many stamens {s) ; the niamerous 

 small carpels constituting the gynaecium are inserted upon the 



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