PRIMULACEAE 



73 



1819. P. farinosa L. (Darwin, 'Forms of Flowers,' pp. 45, 224, 273 ; Herm. 

 Miiller, ' Alpenblumen,' pp. 363-7 ; IVIacLeod, ' Pyreneenbl.,' p. 372.) This species 

 bears dimorphous heierostylous butterfly or humble-bee flowers. It is of particular 

 interest because in the Alps, where Lepidoptera abound, it is adapted to butterflies, 

 while in North Pomerania, where Lepidoptera are relatively few and bees abundant, 

 it is adapted to the latter. Herm. Miiller gives the following differences between 

 flowers from the two regions. (i) Alpine plants bear flowers which are usually 

 larger and more brightly coloured than in Pomerania. (2) In Pomeranian plants, on 

 the other hand, the corolla-lobes are on the average somewhat broader. (3) In 

 Pomeranian plants, as a rule, the 



opening of the corolla and its tube 

 are markedly wider. {Cf. Fig. 245.) 



In Greenland, according to Abro- 

 meit ('Bot. Ergeb. von Drygalski's 

 Gronlandsexped.,' pp. 39-40), the var. 

 mtstassinica (Mchx.) Pax occupies a 

 middle position between P. farinosa, 

 var. typtca, and P. stricta Hornem. The 

 flowers are homostylous, an oeco- 

 logical peculiarity shared with Meny- 

 anthes trifoliata in the same country, 

 for the European type-forms of both 

 plants are heterostylous. 



Visitors. Herm. Miiller ob- 

 served 42 Lepidoptera, 3 Bombyliids, 

 2 Syrphids, a humble-bee, and a wasp 

 in the Alps. MacLeod saw 2 Lepi- 

 doptera, and a Bombyliid in the 

 Pyrenees. 



1820. P. minima L. (Herm. 

 Miiller,' Alpenblumen,' p. 369 ; Schulz, 

 'Beitrage,' II, pp. 148, 223; Kerner, 

 ' Nat. Hist. Pi.,' Eng. Ed. i, II, p. 396.) This species bears dimorphous heterostylous 

 butterfly flowers. The tube of the rose-red corolla is lined with hairs, and is 

 10-12 mm. long with a contracted opening, so that only the proboscis of a 

 lepidopterous insect can conveniently reach the base of the flower. Kerner says that 

 automatic self-pollination is possible in the short-styled flowers by fall of pollen. 



Visitors. Schulz observed Lepidoptera. 



1821. P. longiflora All. (Darwin, ' Forms of Flowers,' p. 50 ; Herm. Muller, 

 'Alpenblumen,' p. 369; Schulz, ' Beitrage,' II, pp. 146-7, 223; Pax, Bot. Jahrb., 

 Leipzig, X, 1888, p. 227 ; Ricca, Atti Soc. ital. sc. nat., Milano, xiii, p. 260; Kerner, 

 ' Nat. Hist. PI.,' Eng. Ed. i, II, pp. 396-7.) This species bears diurnal hawk-moth 

 flowers, described by Darwin as homostylous, and by Ricca and Pax as protandrous. 

 The corolla-tubes are 16-24 mni- long, so that only diurnal hawk-moths are able to 

 suck all the nectar from the longest of them. 



Fig. 245. Primula farinosa, L. (after Herm. Muller). 



A. A short-styled flower from the Alps, seen from above. 



B. Do., partly dissected, and the limb of the corolla bent 

 upwards. C. A long-styled flower, partly dissected (X 2J). 

 D. Average width of the entrance of long-styled flowers 

 from North Germany. E. Do. of short-styled flowers. 

 F. Do. of long-styled Alpine flowers. G. Do. of short- 

 styled Alpine flowers, a, anthers; st, stigma. 



