LENTIBULARIACEAE 237 



2198. P. villosa L. (Warming, ' Arkt. Vaxt. Biol.,' pp. 27-31.)— This species 

 bears flowers possibly belonging to class L. Warming, who examined their mechanism 

 at Besekop, states that they are rather small, with a very narrow spur and entrance, 

 so that only the thin proboscis of a Lepidopterid can penetrate to their interior. The 

 front margin of the anterior stigma-lobe touches the pollen of the anthers, which ripen 

 at the same time, and automatic self-pollination is therefore inevitable. Warming also 

 frequently observed that pollen-tubes had penetrated into the stigma. 



LXXVII. ORDERG! ESNERIACEAE ENDL. 



Literature. — Fritsch, ' Gesneriaceae,' in Engler and Prantl's 'D. nat. Pflan- 

 zenfam.,' IV, 36 ; Delpino, ' Sugli appar. d. fecondaz. nelle piante autocarp.' ; Ogle, 

 Pop. Sci. Rev., London, ix, 1870, pp. 51-2. 



Fritsch says that the unusual brilliance of colouring exhibited by many flowers 

 of this order (showing, for example, every possible shade of vivid red), together with 

 their zygomorphy, points to the conclusion that they are entomophilous, and many, 

 perhaps, pollinated by humming-birds. They are strongly protandrous. 



681. Episcia Mart. 

 2igg. E. mactilata. — Oliver says that the throat of protandrous flowers of this 

 species (growing in Kew Gardens) is firmly closed. Autogamy is excluded by the 

 position of anthers and stigma, and a bee with a very long proboscis probably brings 

 about pollination by opening the valvular flower. Artificial fertilization was effective. 

 Extra-floral nectaries keep away ants. 



LXXVIIL ORDER BIGNONIACEAE R.BR. 



682. Catalpa. 



Kerner says that the species of this genus possess bilobed sensitive stigmas like 

 those of Mimulus. 



683. Bignonia L. 



Delpino ('Ult. oss.,' p. 149) says that in species of this genus the flowers are 

 protandrous, with stamens and style which move in opposite directions. Self-pollination 

 is excluded, because the stigma-lobes close before pollen from the same flower can be 

 transferred to them. 



684. Martynia Houst. 



As Bignonia (Delpino, ' Sugli appar. d. fecondaz. nelle piante autocarp.,' 

 pp. 32-3; Hildebrand, Bot. Ztg., Leipzig, xxv, 1867, p. 284). 



LXXIX. Q^ViY.'^ ACANTHACEAE ^.m.. 



Flowers protogynous, nectar-yielding, usually brightly coloured, and often united 

 into large inflorescences, being thus adapted to attract visitors. 



G. Beck von Mannagetta (' Orobanchaceae,' in Engler and Brand's ' D. nat. 

 Pflanzenfam.,' IV, 36, p. 127) says that insect visitors cause the pollen to be emptied 



