Chap. I. 



PRIMULA AURICULA. 



43 



Primula auricula.* 



- 



This species is heterostyled, like the preceding ones ; hut 

 amongst the varieties distributed by florists the long-styled 

 form is rare, as it is not valued. There is a much greater 

 relative inequality in the length of the pistil and stamens in 

 the two forms of the auricula than in the cowslip ; the pistil 

 in the long-styled being nearly four times as long as that in 

 the short-styled, in which it is barely longer than the 

 ovarium. The stigma is nearly of the same shape in both 

 forms, but is rougher in the long-styled, though the differ- 

 ence is not so great as between the two forms of the cowslip. 

 In the long-styled plants the stamens are very short, rising 

 but little above the ovarium. The pollen-grains of these 

 short stamens, when distended with water, were barely 

 yAtt of an inch in diameter, whereas those from the long 

 stamens of the short-styled plants were barely rfsr, show- 

 ing a relative difference of about 71 to 100. The smaller 

 grains of the long-styled plants are also much more trans- 

 parent, and before distension with water more triangular 

 in outline than those of the other form. Mr. Scott f com- 

 pared ten plants of both forms growing under similar con- 

 ditions, and found that, although the long-styled plants 

 produced more umbels and more capsules than the short- 

 styled, yet they yielded fewer seeds, in the ratio of 66 to 

 100. Three short-styled plants were protected by me from 

 the access of insects, and they did not produce a single seed. 

 Mr. Scott protected six plants of both forms, and found 

 them excessively sterile. The pistil of the long-styled form 

 stands so high above the anthers, that it is scarcely possible 

 that pollen should reach the stigma without some aid; 

 and one of Mr. Scott's long-styled plants which yielded 

 a few seeds (only 18 in number) was infested by aphides, 



* According to Kerner, our gar- 

 den auriculas are descended from 

 P. pubescent, Jacq., which is a hy- 

 brid between the true P. auricula 

 and hirsuta. This hybrid has now 

 been propagated for about 300 

 years, and produces, when legiti- 

 mately fertilised, a large number 

 of seeds ; the long-styled forms 

 yielding an average number of 73, 



and the short- styled 98 seeds per 

 capsule: see his "Geschichte der 

 Aurikel," ' Zeitschr. des Deutsch- 

 en und Oest. Alpen- Vereins,' Band 

 vi. p. 52. Also 'Die Primulaceen- 



Bastarten,' 'Oest. Bot. ZeitechrifV 

 1835, Xos. 3, 4, and 5. 



t ' Journ. Linn. Soc. Bot./ vol. 

 viii., 1864, p. 86. 



• 



