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74 ANGIOSPERMAEDICOTYLEDONES 



Kerner, however, states that this species is heterostylous, and that the short- 

 styled stocks flower before the long-styled ones. Autogamy by the fall of pollen is 

 possible in the former. 



Visitors. Schulz observed the diurnal hawk-moth Macroglossa stellatarum L. 

 (proboscis 25-8 mm. long). 



1822. P. Allionii Loisel. (?) (Schulz, ' Beilrage,' II, pp. 148-9, 223.) Pax 

 (Bot. Jahrb., Leipzig, x, 1888, p. 230) says that the plant observed by Schulz at 

 San Martino Castrozza, and named as above, is probably P. tirolensis Schott, for 

 P. Allionii Loisel. does not grow there. The flowers are heterostylous. 



Visitors. Schulz observed Lepidoptera. 



1823. P. Auricula L. (Sprengel, 'Entd. Geh.,' p. 102 ; Schulz, ' Beitrage,' II, 

 p. 148; Kerner, 'Nat. Hist. Pi.,' Eng. Ed. i, II, pp. 396-7; Knuth, ' Bloemenbiol. | 

 Bijdragen.') The stocks of this species which bear long-styled flowers come into 

 bloom earlier than those bearing short-styled ones. In the former autogamy takes 

 place towards the end of anthesis, for the corolla falls off and the stigma is self- i 

 pollinated by being drawn through the whorl of anthers. 



Visitors. I observed the brimstone butterfly (Rhodocera rhamni Z.), skg., and 

 Schulz also saw butterflies. 



1824. P. glutinosa Wulf. (Kerner, op. cit.) Autogamy is brought about in 



the long-styled flowers as in the last species. 



1825. P. scotica Hook. ( = P. farinosa Z., according to the Index Kewensis). 

 This species bears homostylous butterfly (.?) flowers. The stigma and anthers are 

 usually at the same level and close together, both on the Dovrefjeld (Lindman) and 

 at Tromse (Warming). In rare cases the anthers are a little higher than the stigma. 

 Automatic self-pollination is therefore unavoidable, and this is eflfective, for the setting 

 of fruits has been observed, but only casual insect-visits (from Lepidoptera). Scott, 

 on the contrary, describes the species as self-sterile. 



Visitors. Vide supra. 



1826. P. stricta Hornem. (Warming, * Bestovningsmaade,' p. 7, * Arkt. Vaxt, 

 Biol.,' pp. 21-5.) This species bears lepidopterid flowers. Warming examined it in 

 Greenland, where he says stigma and anthers are at the same level, so that as the 

 flowers are homogamous, automatic self-pollination is inevitable. In Norway the 

 plant is feebly protandrous, and the stigma is situated at a variable height a little 

 above the anthers. Short-styled flowers have not been noticed. Autogamy is thus 

 rendered more difficult. On the Dovrefjeld only one form has been observed, in 

 which the stigma is somewhat higher than the anthers. Scott describes the species- 

 as heterostylous. 



1827. P. sibirica Jacq. (Warming, 'Arkt. Vaxt. Biol.,' pp. 25-7.) Thi 

 species bears heterostylous or homostylous lepidopterid (?) flowers. Warming ob- 

 served markedly heterostylous blossoms by the Altenfjord, and a homostylous one by 

 the KSfjord, in which the stigma and anthers were at the same level, so that automatic 

 self-pollination was inevitable. 



1828. P. egaliksensis Wormsk. Warming describes this species as homo- 

 stylous. 



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