148 ANGIOSPERMAE—DICOTYLEDONES 



2013. C. Cantabrica L. — 



Visitors. — Schletterer observed 5 bees at Pola. — 



I. Andrena nana .X". ; 2. Ceratina cucurbitina 7?owz'; 3. Crocisa ti\3.]ot Mor.; 

 4. Halictus variipes Mor. ; 5. H. villosulus K. 



2014. C. Soldanella L. (^rCalystegia Soldanella R. Br.). — The plants of this 

 species examined by MacLeod on the dunes at Blankenberg were gynodioecious. 

 The mechanism of the hermaphrodite flowers is similar to that of C. arvensis. 

 They are rose-coloured, with five longitudinal white streaks, and their diameter is 

 40-50 mm. The style terminates in two thick papillose sligmatic lobes, and the 

 relative length of it and the stamens is very variable. Sometimes the stigma projects 

 as much as 5 mm. beyond the anthers so that automatic self-pollination is impeded ; 

 and sometimes it is at a lower level, so that autogamy is inevitable. There are 

 numerous intermediate stages between these two extremes. 



The female flowers possess a long style and short stamens, of which the 

 anthers are the same in form as in hermaphrodite blossoms, but do not dehisce 

 and dry up from the base. Both kinds of flower are fertile. 



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

 Stated. — 



MacLeod, a small bee and the earwig (dvg. the anthers), as unbidden guests. 

 H. de Vries (Netherlands), 2 humble-bees — Bombus agrorum F. 5, and B. terrester 

 L. 5 (Ned. Kruidk. Arch., Nijmegen, 2. Ser., 2. Deel, 1875). 



2015. C. siculus. (Kerner, ' Nat. Hist. PI.,' Eng. Ed. i, II, pp. 230, 333.) — 

 Kerner states that in this Mediterranean species the style is produced into two long 

 filiform stigmas. One of these is vertical and forms a direct continuation of the 

 style, while the other diverges at an angle of 60°, and is disposed like a barrier 

 at the entrance of the flower. The stamens are applied to the style, and when 

 the corolla expands their anthers lie on the upright stigma, though when dehiscence 

 takes place autogamy is at first hindered, for the clefts of the anthers are turned 

 outwards, so that insects probing for nectar remove the pollen and transfer it to 

 the transverse stigma of the next flower visited. Later on the anthers shrivel up, 

 and get covered all over with pollen, which is unavoidably transferred to the upright 

 stigma, thus rendering autogamy ultimately possible. 



2016. C. tricolor L. — The flowers of this Mediterranean species, which is- 

 cultivated in Germany, are ephemeral. Kerner says that they open about 7-8 a.m., 

 closing again about 6-8 p.m. Comes (' Ult. stud.') describes them as self-fertile. 



619. Ipomoea L. 



2017. I. purpurea Roth. (Burgerstein, Ber. D. bot. Ges., Berlin, vii, 1889; 

 Kerner, ' Nat. Hist. PI.,' Eng. Ed. i, II, p. 336.) — Cultivated plants of this species 

 examined by Burgerstein and Kerner were protogynous. The stamens are usually 

 applied to the style, and being of different lengths the anthers do not lie side by side, 

 but collectively afford a relatively long surface where pollen is present. At first 

 automatic self-pollination is hindered, not only on account of protogyny, but also 

 because the stigmas project beyond the anthers. Darwin and Kerner, however, sav 



