172 ANGIOSPERMAE—DICOTYLEDONES 



sides of the bases of the stamens. The small petals project from the calyx but little 

 or not at all. In Greenland plants self-pollination is inevitable. They develop fruits 

 as far as 70° or 71° N. lat. Lindman was able to distinguish two varieties in Norway, 

 the larger of which possessed a greater proportion of female flowers, with enclosed 

 dirty red petals and shorter stamens ; while the smaller variety had more male flowers, 

 with projecting expanded petals of yellow colour, and longer stamens. Warming 

 observed in Nova Zemlia a variety intermediate between these two forms, with petals 

 of medium length, and capable of autogamy. The same observer saw in Greenland 

 and Norway flowers that looked normal, but had no pollen and were therefore female. 

 According to Ekstam, Nova Zemlian plants agree with those native to Greenland 

 (Loew, 'Bliitenbiol. Floristik,' p. 100). 



Andersson and Hesselman ('Bidrag till Kanned. om Spetsbergens o. Beeren Eil. 

 Karlvaxtflora,' p. 55) state that the arctic variety of this species (Wahlbergella 

 apetala Fr., var. arctica Th. Fr.) flowers in Spitzbergen from the beginning of July 

 to the middle of August, regularly setting fruits in the latter month. As a rule the 

 plant only bears one flower, or more rarely two. The calyx is dark red — in plants 

 from Greenland (Abromeit, 'Bot. Ergeb. von Drygalski's Gronlandsexped.,' p. 15) 

 with reddish-violet veins on a green ground — and the scarcely longer corolla dirty 

 violet. The entrance of rain is prevented by the pendulous nature of the flower, and 

 by its narrow opening. The pollen-grains are normal, and quickly germinate in 

 distilled water. Self-pollination is the rule, for the anthers are in immediate contact 

 with the twisted stigmas. 



Ekstam (' Bliitenbiol. Beob. a. Spitzbergen,' p. 24) describes the plant as dio- 

 ecious (?), perhaps on the strength of two somewhat different sexual forms observed 

 by Lindman on the Dovrefjeld, He only makes special mention, however, of her- 

 maphrodite and female flowers. 



Visitors. — Ekstam saw none in Spitzbergen. 



431. M. involucrattun Cham, et Schlecht, var. BafBne Rohrb. (= Wahlbergella 

 afifinis Fries.). — This plant has been studied by Warming in Greenland. The faintly 

 odorous flowers possess more or less projecting petals. It is doubtful whether they 

 belong to Class L. The flowers are at first protogynous, but automatic self-pollina- 

 tion is possible in the later stages of anthesis. Fruits are ripened as far as 70° or 71° 

 N. lat., and — in Grinell Land in Arctic America — even as far north as 84°; they 

 have also been found in Spitzbergen and Nova Zemlia. In Norway purely female 

 flowers have been observed (Loew, op. cit.). 



According to Andersson and Hesselman (op. cit., p. 56), this species flowers in 

 Spitzbergen from the middle of June on. Ripe fruits were collected by Ekstam on 

 August 7, 1897. The plants usually bore only one or two flowers, rarely three. 

 The petals project beyond the cylindrical calyx for §-A its length. Ekstam (op. cit., 

 p. 25) determined the diameter of the flowers to be 12-13 mm. I'^e hermaphrodite 

 blossoms are protogynous to homogamous, and secrete nectar on the inner sides of 

 the bases of the filaments. 



Visitors. — Ekstam observed none in Spitzbergen, 



432. M. triflorum J. Vahl. — According to Warming, who studied this northern 

 species in Greenland, it is doubtful whether it belongs to Class L. The flowers are 



