LABI ATA E 265 



A. Hymenoptera. Apidae: i. Apis mellifica L. 5, trying to suck; 2. Bombus 

 terrester L. t, skg. ; 3. Psithyrus vestalis Fourcr. i, do. B. Lepidoptera. 

 Rhopalocera : 4. Pieris brassicae L. ; 5. Vanessa urticae Z. ; both skg. On the var. 

 purpurea 3 bees — i. Bombus agrorum F. S, skg. legitimately ; 2. B. terrester L. S, 

 do. ; 3. Psithyrus vestalis Fourcr. S, skg. 



707. Ramona. 



2275. R. polystachya (Benth.) Greene. (Rippa, Boll. Soc. nat., Napoli, xv, 

 1902, pp. 51-3.) — Rippa examined plants of this species (indigenous to Colorado) 

 cultivated at Naples. As compared with the related genus Salvia there is a marked 

 reduction of the lower lip, and the anterior limbs of the connectives are vestigial. 

 Hairs within the corolla-tube serve as a nectar-cover, and the large lower lip is 

 hispid. A bee forcing its way into the flower gets irregularly dusted with pollen 

 laterally, and forces the style strongly to the side so that autogamy takes place. 

 The lower lip subsequently erects itself, so that a visitor is obliged to depress it in 

 order to get at the nectar, and in doing so describes a lateral movement by which 

 any pollen it brings can be deposited on the stigma. Allusion must also be made to 

 the presence of sticky drops on the surfaces of the anthers and sides of the 

 connexions (according to SoUa, referred to op. cit.). 



708. Origanum Toum. 



Protandrous hermaphrodite flowers; with nectar secreted by the large base of 

 the ovary, concealed in the glabrous bottom of the corolla, and protected from rain 

 by a ring of hairs. Often gynodioecious and gynomonoecious. 



2276. O. vulgare L. (Darwin, ' Cross- and Self-fertilisation,' p. 94; Herm. 

 Miiller, 'Fertilisation,' pp. 475-6, ' Weit. Beob.,' Ill, pp. 57-8, ' Alpenblumen,' 

 p. 322; Kirchner, 'Flora v. Stuttgart,' p. 611; Schulz, ' Beitrage ' ; Kerner, ' Nal. 

 Hist. PI.,' Eng. Ed. i, II, p. 298; Knuth, ' Bloemenbiol. Bijdragen.')— The 

 hermaphrodite flowers of this species are large (about 7 mm. long) and protandrous, 

 the female considerably smaller (4-5 mm. long). Schulz says that, sporadically, 

 the latter are as numerous as the former. Willis found about 6 % female flowers 

 near Cambridge. Kerner states that these open a week or more before the 

 hermaphrodite ones, and he therefore describes them as protogynous. He adds 

 that in a circuit of some km. no pollen is available for the stocks which flower 

 first. The dull-purple flowers grow in dense half-whorls, crowded into cymose 

 spikes ; this makes them very conspicuous, and they are much visited by insects. 

 Stamens and style project from the flower, but self-pollination is prevented by 

 protandry. In female flowers the anthers are often completely absent. Visitors 

 belong to very various groups. They may be insects with quite a short proboscis, 

 as the corolla-tube is fairly wide and very short (in hermaphrodites 4-5 mm., in 

 females 3-4 mm.). Various parts of their bodies are dusted with pollen, and 

 touch the stigma irregularly with first one part and then another, thus effecting 

 crossing. 



Visitors. — Herm. Miiller (H. M.) and Buddeberg give the following list for 

 Central Germany. — 



