PRIMULACE^. 137 



proof that these three are all forms of one species, as there is no ground 

 for supposino- that precautions were taken to prevent the pollen of the 

 primrose bemg conveyed to it by insects ; and j\Ir. Darwin has shown 

 that a single plant of either the cowslip or primrose is nearly sterile 

 unless it is fertilised by the pollen from another individual. It is doubt- 

 less from this cause that the oxlip, when cultivated in a garden, as was 

 done by Mr. Hewett C. Watson, yields seeds which produce all forms 

 from the primrose to the cowslip-oxlip : indeed, it is probably only 

 accidental that the cowslip itself was not raised by him from the seeds 

 of the oxlip. Interesting matter on this subject will be found in tlie 

 first series of the Ptylologist, vol. ii. pp. 217, 852, in which ]\Ir. Watson 

 details the results of his experiments. See also ]\lr. Darwin's paper, 

 in the Joui'ual of the Pi'oceedings of the Linno'an Society, Botany, 

 vol. vi. p. 77. 



Common Oxlip. 



Great discussions have arisen amongst botanists as to wlietlier the primi'ose and the 

 cowslip be really distinct, and a long-standing confusion seems to have existed with 

 regard to the " Oxlip." This plant is frequent in the cowslip and primrose districts, 

 growing with the former in the open fields, though always as a solitary individual. 

 It is a great favourite in cottage gardens, and in many respects resembles both tho 

 cowslip and the primrose. There appears to be good evidence that the Oxli2} is a 

 mule or hybrid between the cowslip and primrose, the result of bees and other insects 

 conveying the pollen from one kind of flower to the pistil of tke other ; as gardeners do 

 when they hybridise plants artificially. Moreover, on the Continent, where the cowslip 

 and primrose are said to be rarely seen together, this "common Oxlip " appears to 

 be unkno\m. There the primrose is rather a southern plant, extending from France 

 to the confines of Asia, while the cowslip is more of a northern one, extending as far 

 as Finland. Both pi'imrose and cowslip occur, it is true, near together beyond the 

 Alps, but the former is always as a plant of warm valleys, the latter as one of moun- 

 tains, and too far apart from one another to hybridise. Their intermixture in England 

 is a lively type of the twofold nature of our climate, and it is not surprising that they 

 should issue in a form partaking of the characters of both species. The garden flowers 

 belonging to this family of primroses are very numerous and attractive, and include 

 the numberless varieties of Polyanthus, Auriculas, and Cyclamens. The exquisite 

 velvety sui-face of the leaves of the Auriculas, and the deep royal purple or crimson 

 colour of the flowers, are peculiarly atti-active and beautiful. 



"Auriculas cm-ich'd 

 With shining meal o'er all their velvet leaves." 



Section II.— ALEURITA. Duhy in part. 



Calyx without angles, rather shorter than the tube of the corolla. 

 Bracts of the involucre saccate at the base. Leaves not evergreen, 

 nearly smooth, mealy beneath, with revolute margins when young. 

 Plant in winter reduced to a bulb-like bud. 



VOL. VII. T 



