106 FOUNDATIONS OF BOTANY 
A. 
Ripe carpels not enclosed within the calyx-tube. 
1. Fruit dry. 
(a) Carpels 1-5, inflated. Physocarpus, I. 
(b) Pods 5-8, not inflated. Spireea, II. 
(c) Akenes 2-6, styles not lengthening after flowering. 
Waldsteinia, VIII. 
(d) Akenes many, on a dry receptacle. Styles not length- 
ening. Potentilla, X. 
(e) Akenes many, on a dry receptacle. Styles lengthening 
after flowering, forming tails to the akenes. 
Geum., XI. 
2. Fruit fleshy. 
(a) Akenes several-many, becoming little stone-fruits. 
Rubus, VII. 
(6) Akenes many, dry on ripening, on a fleshy, eatable 
receptacle. Fragaria, IX. 
(c) Pistil solitary, becoming a stone-fruit. Prunus, XIII. 
Fic. 13. — Pistils in the Rose Family. 
A, Prunus-type; B, Potentilla-type ; C, Rosa-type, c, calyx, 0, ovary. 
B. 
Ripe carpels enclosed within the calyx-tube. 
1. Fruit a pome. 
(a) Carpels more than 2-seeded; seeds covered with a muci- 
laginous pulp. Fruit 5-celled. Cydonia, III. 
