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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



1. Habit of growth. — Contrast the long scrambling stems of 

 B. arvensis, or BanJcsice, with the arch springing from the 

 erect pillar of canina or indica and the short, stiffly erect stems 

 of cjallica and villosa. 



2. Armature. — Prickles vary in shape, from the parrot's-beak 

 prickle of sinica and canina to the straight, slender prickle of 

 spinosissima and villosa. In some species the principal prickles 

 are in regular pairs at the base of the leaf ; in some they are 

 uniform in size, but scattered irregularly, whilst in other species 

 they are crowded and very unequal. There is no hard and sharp 

 line of demarcation between aculei, aciculi, and gland-tipped 

 seta. In some species the peduncles and pedicels are naked, and 

 in others beset with aciculi and setae. One of the best characters 

 by which to distinguish the garden Koses that are descended from 

 cjallica from those that are descended from indica is the irregu- 

 larity of the prickles of the former. 



Stipules often furnish excellent characters. For instance, in 

 multiflora they are deeply fimbriated. B. Banksice differs from 

 all the other Eoses in the stipules not being adnate to the base 

 of the petiole, and consequently deciduous. 



Leaves. — One species, often regarded as a distinct genus, has 

 simple leaves. B. sinica has three leaflets. The usual number is 

 five or seven. In microphylla they get up to eleven or thirteen. They 

 vary of course greatly in texture, shape, toothing, and vestiture. 



Inflorescence and bracts. — There is a good deal of character 

 in bracts and inflorescence. In some species the flowers are 

 essentially solitary. In B. Banksice they are umbellate, and 

 the pedicels have no bracts. In the other species the inflores- 

 cence is a few- or many-flowered corymbose cyme. 



Parts of the flower. — The normal symmetry is pentamerous. 

 The Indian B. sericea is typically tetramerous, and was there- 

 fore called Bosa tetrapetala by Royle. 



Calyx. — There is a great deal of character in the calyx. The 

 calyx-tube differs greatly in shape. Sometimes, often even in 

 the same species, it is naked, sometimes bristly. The calyx 

 segments differ widely in character. Sometimes they are entire, 

 sometimes copiously pinnatifid, sometimes produced into long 

 leafy points. In some species they fall as soon as the tube 

 begins to turn red, in others they are subpersistent, and in others 

 they remain till the tube turns perfectly red and pulpy. In our 



