O N O 



O N O 



covered by mats in the winter frost, great care 

 must be taken to prevent llicir becoming mouldy, 

 by not letting them remain covered too long, 

 without the air i_>eing admitted. 



They flower and produce fruit sometimes in 

 two or three vears. 



They all afford variety among other green- 

 house plants as well a.» in other situations. 



OLIVE. See Olea. 



ONONIS, a genus containing plants of the 

 shrubby kind. 



It belongs to the class and order Diadelphia 

 Dccandrla, and ranks in the natural order of 

 Pap'ilionacece or Leguminosce. 



The characters are : that the calyx is a five- 

 parted perianthium, almost the length of the 

 corolla : segments linear, acuminate, slightly 

 arched upwards ; the lowest under the keel : the 

 corolla is papilionaceous : banner cordate, stri- 

 ated, depressed at the sides more than the other 

 petals : wings ovate, shorter bv half than the 

 banner . keel acuminate, as long as or longer 

 than the wings: the stamina have ten filaments, 

 connate in an entire cylinder : anthers simple : 

 the pistillum is an oblong germ, villose : style 

 simple, rising : stigma blunt : the pcricarpium 

 is a rhomb-shaped legume, turgid, subvillose, 

 one-celled, Iwo-valved, sessile : the seeds few 

 and kidney-form. 



The species principally cultivated are : 1. 0. 

 Nafri.r, Yellow-flowered Shrubby Rest-harrow; 

 2. 0. tridentattt, Three-toolh-leaved Rest-har- 

 row ; 3. 0. fruticosa, Shrubby Rest-harrow; 

 4. 0. rotundif'oHa, Round-leaved Rest-harrow. 



There are other species both of the annual 

 and perennial kinds, that may be cultivated for 

 variety. 



The first is a very strong-smelling plant, with 

 a resinous odour, and not very clammy : tlie 

 leaves oval, flattish, serrate only at the top, not 

 fleshy : the peduncle the length of the awn : 

 root large and wrinkled: the stems more or less 

 upright, commonly a foot high : leaflets oblong, 

 villose, toothed at the end : the flowers large, 

 yellow, solitary, on a peduncle elbowed at two- 

 thirds of its length, whence springs a thread 

 like an awn : the upper part of the flower is 

 rayed with red lines: legumes oblong and vil- 

 lose. It is a native of the South of France, 

 &c. 



The second species has erect shrubby stalks, 

 a foot and a half high, dividing into slender 

 branches very full of joints : the Icafiets are 

 narrow, thick, flcshv, on short footstalks : the 

 flowers at the ends of the branches in loose pa- 

 nicles, some of the peduncles sustaining two 

 and others but one flower : they are of a fine 

 purple colour, and appear in June; the seeds 



ripening in September. It is a native of Spain 

 and Portugal. 



The third species is a very beautiful low 

 shrub, ri-ing with slender stalks about two feet 

 high, dividing into many branches : the flowers 

 come out in panicles at the ends of the branches 

 upon long peduncles, which for the most part 

 sustain three large purple flowers : the legumes 

 are turgid, about an inch long, hairy, inclosing 

 three or four seeds. It is a native of the South 

 of France, flowering in May and June. 



It varies with white flov,-ers. 



The fourth has the stem round, striated, 

 somcwliat villose, a foot and half or two feet 

 in height : the leaves are petioled, serrate-tooth- 

 ed, with the teeth alternately larger and smaller, 

 villose, large ; the end leaflet larger and rounder 

 than the others : the stipules green, sheathing, 

 obsoletely serrate, with longitudinal prominetit 

 nerves : the flowers form handsome bunches at 

 the ends of the branches ; they are on a long- 

 peduncle, frequently three together, each on its 

 proper pedicel, of a purple colour. It is a 

 native of Switzerland, flowering from Mav to 

 July. 



Cidiure. — These plants may be increased by 

 seeds, cuttings, and slips, according to the 

 different kinds. 



The seeds of the first sort should be sown 

 upon beds of light earth in the early spring, as 

 about April, thinly in drills, when they should 

 be properly thinned out during the summer 

 months, and kept perfectly free from weeds ; 

 when in the beginning of the autumn they may 

 be removed into the places where they are to 

 remain. It may likeuise be increased by cuttings 

 planted out at the same time. 



Though this sort is pretty hardy when the 

 winters are not very severe, a fevv plants should 

 always be kept in the green-house. And as it 

 is apt to grow out of form it should be kept well 

 cut iri, and new plants be frequently raised 

 from seeds. 



These plants cannot be preserved in pots. 

 They flower the second vear. 



The second sort should have the seeds sown 

 in pots and placed in a mild hoi-bed, or on 

 a very warm sheltered border, in the early 

 spring ; but the first is the best method, the 

 plants being afterwards managed as tender 

 ]ilants, having either t!ie protection of the green- 

 house or of mats. 



The third sort is raised from seeds sown cither 

 in pots or warm borders in the early spring 

 months. It succeeds best in shady situations 

 where the soil is of a sandy quality. The pot- 

 ted plants are often inlrodnced in green-house 

 collections ; but they are capable of with- 



