PERICARP. 



113 



551. POROUS dehiscence is exemplified in the poppy, where the seeds 

 escape by orifices near the top of the fruit. It is not common. 



552. CIRCUMSCISSILE (circumscindo, to cut around), when the top 

 of the ovary opens or falls off like a lid, as in Jeffersonia, henbane, 

 plantain. 



553. CARPOPHORE. Some fruits, as the Gerania and Umbeliferse, are 

 furnished with a carpophore, that is, a slender column from the recep- 

 tacle, prolonged through the axis of the fruit, supporting the carpels. 



554. THE MORPHOLOGY of the pericarp is exceedingly diversified, but it will suf- 

 fice the learner at first to acquaint himself with the leading forms only, such as are 

 indicated in the following synopsis and more definitely described afterward. 



555. The following is a synopsis of the principal forms of Pericarps. 



1. FREE FRUITS (FORMED BY A SINGLE FLOWER). 



* PERICARPS INDEHISCENT, 



f With usually but one seed, and 

 \ Uniform, or l-coated. 



1. Separated from the seed. Achenium (buttercups). 



2. Inflated, often breaking away. Utricle (pigweed). 



3. Inseparable from the seed. Caryopsis (grasses). 



4. Invested with a cupule (involucre). Glans (oak). 

 6. Having winged appendages. Samara (ash). 

 Double or triple-coated, fleshy or fibrous. 



6. Three-coated. Stone cell entire. Drupe (cherry). 



7. Two-coated. Stone cell 2-parted. Tryma (walnut). 



8. Drupes aggregated. Etaerio (raspberry). 

 \ With two or more seeds, 



% Immersed in a fleshy or pulpy mass. 



9. Rind membranous. Berry (gooseberry). 



10. Rind leathery, separable. Hesperidium (orange) 



11. Rind hard, crustaceous. Pepo (squash) 

 \ Inclosed in distinct cells. Pome (apple). 



* PERICARPS DEHISCENT. 



12. Dehiscence circumscissile. seeds oo . Pyxis (henbane), 

 f Dehiscence valvular or porous ; 



\ Simple or 1-carpeled, 



13. Opening by the ventral suture. Follicle (columbine). 



14. Opening by both sutures. Legume (pea). 



15. Legume jointed. Loment (Desmodiura). 

 J Compound pericarps; 



16. Placenta? parietal with two cells. Silique (mustard). 



Silique short. Silicle (shepherd's purse). 



17. Placentae parietal only when 1-celled. Capsule (flax). 



18. Capsule with carpophore and elastic styles. Regma (Geranium). 



2. CONFLUENT FRUITS (FORMED OF AN INFLORESCENCE). 



* With open carpels aggregated into a cone. Strobile (pine). 



* With closed carpels aggregated into a mass, as in the fig. mulberry, Osage-orange, 



pine-apple, etc. 



