258 



PRACTICAL COURSE IN BOTANY 



has happened. The placentas are greatly enlarged and 

 modified, and it may be necessary to refer to the diagram, 

 Fig. 372, c, in order to make them out. How many locules, 

 or chambers, are there in your specimen? How many 

 placentas? Notice that these are central 

 and double, but extend to the pericarp be- 

 fore dividing so that they appear to be pa- 

 rietal, and twice their real number, which 

 is only three. Are the seeds vertical, as in 

 the apple, or horizontal? Look for the 

 little stalk, or thread, that attaches them 



of the carpels in dia- 

 gram. (After GRAY.) 



FIG. 372. Cross 

 section of gourd : c, one tO the placenta. 



Pepo is the name given by botanists to 

 this kind of fruit. Write in your notebook 

 a proper definition of it, from'the specimens examined. 



291. The berry. Examine a tomato, an eggplant, a 

 grape, cranberry, lemon, or orange, in both cross and ver- 

 tical section, and compare it with the melon and the apple. 

 What differences and resemblances do you find? Cut a 

 cross section, and draw, showing the attachment of the seeds. 

 How many locules are there? Normally the tomato is a 

 two-celled fruit, like the potato berry (Fig. 374), but it has 

 been so modified by cultivation that 

 the original plan is not always easy 

 to distinguish. See if you can make 

 it out. Do the seeds in your speci- 

 men appear to be healthy and well 

 developed, or are some of them small 

 and aborted ? How do you account 

 for this? (285,286.) What differ- 

 ence do you notice in color between 

 the ripe and unripe fruit ? Write a 

 definition of the berry from the study you have made of it. 



Berries are the commonest of all fleshy fruits, and the most 

 variable and difficult to define. In general, any soft, pulpy, 

 or juicy mass, like the grape and tomato, whether one or 



373 



374 



FIGS. 373, 374. A potato 

 berry : 373, exterior ; 374, cross 

 section. 



