112 ANGIOSPERMAE—DICOTYLEDONES 



Norway), the humble-bees Bombus pratorum Z. 5, and B. terrester Z. 5 (Tromso, 

 Mus. Aarsheft., 1894). 



1934. P. humile Willd. (=P. pulchellum Bungi). (Ekstam, 'Bliitenbiol. 

 Beob. a. Spitzbergen,' pp. 8-9, Bot. Jahrb., Leipzig, xxii, 1897, p. 185; Andersson 

 and Hesselman, ' Bidrag till Kanned. om Spetsbergens o. Beeren Eil. K'arlvaxtflora,' 

 pp. 17-18.) — Ekstam says that in Nova Zemlia this species exhales a strong 

 and extremely unpleasant goat-like odour. The flowers are homogamous, and 

 the nectar secreted in their bases is protected by glandular hairs lining the 

 corolla-tube. 



The plants observed in Spitzbergen by Andersson and Hesselman, also by 

 Ekstam, bear blue or sometimes white flowers, which either possess a sweet smell 

 suggesting that of Viola lutea, or a disagreeable musky one. At the opening 

 of the corolla-tube there is an orange-yellow nectar-guide with a violet margin. 

 There is a hypogynous annular nectary, the secretion of which is protected by 

 long hairs on the bases of the filaments. The pollen -grains are normally 

 developed, and rupture in a few minutes when placed in distilled water. The 

 pollen is protected against damp partly by the position of the flowers, and partly 

 by the facility with which the thin petals fall together during rain. Ekstam 

 found marked protogyny in some cases, though homogamy is the general rule. 

 The anthers are situated at a slightly higher level than the stigmas, so that 

 autogamy is easily possible. The plant flowers in Spitzbergen from the end of 

 June till the beginning of August, but in spite of this early anthesis fruits do not 

 always ripen. 



Visitors. — Ekstam observed medium-sized flies in Nova Zemlia, and also 

 a hybrid P. humile Willd. x P. caerulem Z., indicating insect-visits. In this 

 cross 90 % of the pollen-grains were abortive. No visitors were observed in 

 Spitzbergen. 



587. Phlox L. 



Protandrous Lepidopterid flowers. 



1935. P. paniculata L. (Sprengel, 'Entd. Geh.,' pp. 105-6; Herm. Miiller, 

 ' Fertilisation,' p. 407 ; Knuth, ' Bloemenbiol. Bijdragen,' ' Weit. Beob. ii. Bl. u. 

 Insekt. a. d. nordfr. Ins.,' p. 238,) — In this species nectar is secreted at the base 

 of the ovary, and stored in the corolla-tube, which is 18-22 mm. long and 3 mm. 

 broad at its centre. The dehisced anthers are situated in the entrance of the 

 corolla-tube when the flower opens, and the still apposed stigmas about its centre. 

 While the anthers are being robbed of their pollen, the style gradually elongates 

 till it reaches their level, when the stigmas diverge and expose their papillose 

 inner surfaces. Insect visitors will consequently transfer pollen from younger 

 flowers to the stigmas of older ones. 



Visitors. — The following were recorded by the observers, and for the locahties 

 stated. — 



Knuth (gardens at Nieblum, Fohr, 22. 7. '23), the diurnal hawk-moth visiting 

 numerous flowers in succession; (his own garden at Kiel), the same moth. The 

 form of the corolla-tube corresponds to that of the moth's proboscis, being slightly 



