112 ANGIOSPERMAE—DICOTYLEDONES 



In Dumfriesshire (Scott-Elliot, 'Flora of Dumfriesshire,' p. i6) a Muscid and 

 Meligethes have been recorded. 



In Spitzbergen Ekstam only saw a medium-sized Dipterid. 



271. C. arctica Schlecht. — Ekstam says that in Nova Zemlia self-pollination 

 is brought about by the closing of the flowers. 



272. C. danica L. (Knuth, ' Bl. u. Insekt. a. d. nordfr. Ins.,' ' Bl. u. Insekt. a. 

 Helgoland.') — The diameter of the flower is only 4-5 mm. I could find no nectaries. 

 The anthers of the long stamens dehisce first, but from the beginning they are 

 directed towards the stigma, projecting a little beyond it. Those of the short 

 stamens dehisce soon afterwards, and then all the anthers incHne towards the 

 middle of the flower, thus effecting automatic self-pollination, provided that autogamy 

 or allogamy has not previously resulted from insect-visits. Autogamy is effective in 

 any case. 



Visitors. — In Schleswig-Holstein I observed (' Bl. u. Insekt. a. d. nordfr. Ins.,' 

 p. 149) flies — Syrphidae and Muscidae — and also a nect.-lkg. ant. On Helgoland 

 (Bot. Jaarb. Dodonaea, Ghent, viii, 1896, p. 38) I also saw the following: Syrphidae: 

 I. Eristahs sp. ; 2. Syritta pipiens L. Besides these I noticed — on June 5, 1897 — 

 minute Muscidae persistently working in the bases of the flowers, and obviously 

 getting sap ; but I did not succeed in repeating the observation. 



273. C. groenlandica L. — Warming states that there are two non-functional 

 nectaries. The anthers do not touch the stigma — which matures simultaneously — 

 but autogamy takes place, apparently by closing of the flower at night or during 

 unfavourable weather. It must be effective, for numerous fruits are set. Kerner 

 says that autogamy is brought about as in Schievereckia. (See p. 107.) 



81. Eutrema R. Br. 



274. E. Edwardsii R.Br. — Ekstam states that the odourless flowers are homo- 

 gamous in Nova Zemlia. Their diameter in Arctic Siberia is usually 5 mm., according 

 to Kjellmann. Self-pollination is possible. 



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

 Eil. Karlvaxtflora,' p. 34) that this arctic species ceases flowering in Spitzbergen 

 in the middle of July, but it is not known whether ripe fruits are produced. 

 Vanhoffen found a fruiting plant in Greenland on August 20, 1892 (see Abromeit, 

 'Bot. Ergeb. d. Drygalski's Gronlands-Exped.,' p. 27). 



82. Catnelina Crantz 



Yellow horaogamous flowers with half-concealed nectar. Four nectaries. 



275. C. sativa Crantz (=C. microcarpa An rz.). (Kirchner, ' Flora v. Stuttgart,' 

 p. 306; Warnstorf, Verh. bot. Ver., Berlin, xxxvii, 1895, and xxxviii, 1896; Knuth, 

 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 29-30, ' Bloemenbiol. Bijdragen.') — There are 

 four nectaries, two outside the base of each short stamen. The diameter of the corolla 

 is only 4 mm. The anthers of the long stamens are at the same level as and very 

 close to the stigma, so that they can effect self-pollination. Those of the short stamens 

 are lower than and curved outwards away from the stigma. They serve for cross- 



