412 



ANGIOSPERMAE—DICOTYLEDONES 



977. C. tetrandrum Fries (= C. alternifolium, according to the Index 

 Kewensis). (Warming, ' Arkt. Vaxt. Biol.,' pp. 4-7.) — Warming investigated plants 

 from Spitzbergen. The flowers are greenish, less open than in C. oppositifolium, 

 and with a scarcely developed nectary. Besides homogamy, slight protandry was 

 observed. Automatic self-pollination regularly obtains by contact of the stigmas with 

 the anthers of the two outer stamens. This must be effective, for almost every 

 flower sets fruit. 



Fig. 133. Chrysosphnium tetrandrum. Fries (after E. Wanning). .^4. Longitudinal section through 

 an almost closed flower. Anthers unripe, styles short. B. Do. through a fully open young flower. The 

 stigmas touch some of the ripe anthers, which deposit a quantity of pollen upon them (cf. D). C. A 

 fenilized flower. The formation of seeds and setting of fruit have begun ; the free parts are more erect, 

 and have closed in somewhat. D. Style of i? more highly magnified, showing the stigma covered with 

 numerous pollen-grains. E, F. Sterile stamens, the latter in connexion with its perianth leaf. G. Longi- 

 tudinal section through a sterile stamen. H. Normal anther. J. Scarcely ripe fruit. K. Do. through 

 a similar fruit ; the seeds have been removed, but some of the funicles are still present in part. (A^ B, C, 

 /, K y. 8.) 



271. Heuchera L. 



978. H. cylindracea Lindl. — 



Visitors. — Loew observed 2 bees in the Berlin Botanic Garden (Apis mellifica 

 L. 5, skg., and Halictus cylindricus F. 5, do.). 



272. Tellima R. Br. 



979. T. grandiflora R. Br. — 



Visitors. — Loew observed a bee (Apis mellifica L. 5) and a butterfly (Pieris 

 brassicae Z.), skg., in the Berlin Botanic Garden. 



273. Tiarella L. 



980. T. cordifolia L. — Francke describes this species as protogynous (' Inaug.- 

 Dissert.,' Halle, 1883). The anthers ripen in succession at long intervals. 



274. Pamassia L. 



Flowers white in colour, markedly protandrous, with half-concealed nectar. 

 There are five fringed glandular staminodes opposite the petals. Each of them 

 swells into a disk, with two shallow depressions on the upper side, into which 

 the tolerably exposed nectar is sparingly secreted. 



