EOSACEAE. 145 



1. G. hirtella (Michx.) Spach. Straggling shrub with pale twigs: leaf -blades 

 1-3 cm. in diameter, finely pubescent, the 3-5 lobes coarsely toothed: hypan- 

 thium glabrous: sepals oblong-ovate, 2.5-3.5 mm. long: petals cuneate, f as 

 long as the sepals: stamens much longer than the sepals: berries 8-10 mm. in 

 diameter, black or purple. — M. Eather rare, in woods and thickets. — Lime- 

 stones. — Spr. — Smooth-gooseberry. 



Family S. PLATANACEAE. Plane-tree Family. 



Trees, with thin smooth bark. Leaves alternate : blades membranous- 

 leathery, palmately lobed. Flowers monoecious, minute, mserted on glo- 

 bose receptacles, in dense pedunculate solitary, spicate, or racemose heads. 

 Perianth obsolete. Staminate heads red: filaments nearly obsolete: 

 anthers elongate, each surmounted by a dilated connective. Pistillate 

 heads green: carj^els 2-9, 1-celled, mingled with staminodia which are 

 pilose at the apex, surrounded by long-jointed persistent hairs: style 

 terminal, stigmatose to below the middle on the ventral suture. Fruit an 

 elongate achene, surrounded by rigid hairs, with a thin leathery pericarp, 

 crowded in dense globose heads. 



1. PLATANTJS [Tourn.] L. Trees, with smooth bark and stout irregular 

 branches from which are suspended the usually numerous long-peduncled fruit- 

 heads. — Plane-tree. Sycamore. 



1. P. occidentalis L. Tree becoming 55 m. tall, the bark pale: leaf -blades 

 3-5-lobed, 10-20 cm. broad, permanently woolly on the veins beneath: fruiting 

 heads subglobose, 2-4 cm. in diameter, drooping. — Common, in low places, 

 usually near streams. — Spr. — Button-wood. Button-ball. 



Family 9. ROSACEAE. Rose Family. 



Herbs, shrubs, trees, or rarely vines. Leaves mostly alternate : blades 

 simple or compound, often stipulate. Flowers perfect or rarely dioecious. 

 Calyx of 5, or rarely 4r-9, sepals borne on the edge of the hypanthium, 

 sometimes accompanied by as many bractlets. Corolla of as many distinct 

 petals as there are sepals, or wanting. Androeeium of 1 or more series 

 of stamens. Gynoecium of 1-many carpels. Ovary 1-celled or imper- 

 fectly 2-celled. Fruit mostly follicles or drupelets, or achenes which are 

 borne in the hypanthium or on the accrescent receptacle. 



Fruit not enclosed in a depressed or hollow hypanthium. 



Rstils few, rarely more than 5, maturing into 2-4-seeded folicles. 



Follicles opening along both sutures : seeds shining. 1. Opl'LAster. 



Follicles opening along one suture : seeds dull or granular. 

 Pistils alternating with the sepals : shrubs with 



simple leaf-blades. 2. Spiraea. 



Pistils opposite the sepals : herbs with 3-parted or 



3-foliolate leaf-blades. 3. Porteranthus. 



Pistils numerous or rarely few, maturing into achenes or 

 1-2-seeded drupelets. 

 Pistils ripening into drupelets crowded on a receptacle. 

 Receptacle flat : ovary pubescent above : drupelets 



crowned with a hairy cushion. 4. Robacer. 



Receptacle convex or conic : ovary glabrous : drupe- 

 lets glabrous. 5. Rubus. 

 Pistils ripening into achenes. 

 Style deciduous. 



Style basal. 6. Drymocallis. 



Style lateral. 



Receptacle pulpy, edible : petals white. 7. Fragaria. 



Receptacle neither pulpy nor edible : petals 



yellow. 8. Duchesnea. 



Lancaster County Flora 10. 



