6i2 SOLANACEAE 



with petals, epipet., or fewer in -|- fls. , often opening by pores; G (2), 

 obliquely placed in the f). (the post. cpl. to the right, the ant. to the 

 left, when shown in a floral diagram), 2-loc., sometimes with secondary 

 divisions (e.g. Datura), upon a hypog. disc; ov. i oo in each loc. , 

 anatr. or slightly amphitr., on axile plac. (most often the plac. are 

 swollen and the ov. numerous) ; style simple, with 2-lobed stigma. 

 Berry or caps. Embryo curved or straight, in endosp. Fls. conspic., 

 insect-visited ; some, e.g, Nicotiana, suited to Lepidoptera. A few 

 are economically important, e.g. Solanum (potato), Nicotiana (tobacco), 

 Lycopersicum, Capsicum, &c. ; Datura, Atropa, &c. are medicinal; 

 several are favourites in horticulture. 



Classification and chief genera (after von Wettstein) : the S. are 

 nearly related to Scrophulariaceae, the most general distinction being 

 the oblique ovary : this however is by no means easily made out, and 

 the zygomorphism of the fl. is most often used as a distinction. Cer- 

 tain genera of S. are nearly related to various Boraginaceae, Gesne- 

 riaceae, Nolanaceae, &c., and it is possible that the S. are not really 

 a simple monophyletic family ; they occupy a middle place between 

 the Tubuliflorae with actinom. and those with zygom. fls. 



A. Embryo clearly curved, through more than a semicircle. All 

 5 sta. fertile, equal or only slightly different in length. 



i. Nicandreae (ovary 3 5-loc., the walls of the loc. dividing the 

 placentae irregularly) : Nicandra (only genus). 



i. Solaneae (ovary 2-loc.) : Lycium, Atropa, Hyoscyamus, Phy- 

 salis, Capsicum, Solanum, Lycopersicum, Mandragora. 



3. Datureae (ovary 4-loc., the walls dividing the placentae 

 equally) : Datura, Solandra (only genera). 



B. Embryo straight or slightly curved (less than a semicircle). 



4. Cestreae (all 5 sta. fertile) ; Cestrum, Nicotiana, Petunia. 



5. Salpiglossideae (2 or 4 sta. fertile, of different lengths): Salpi- 

 glossis, Schizanthus. 



Solandra L. = Hydrocotyle Tourn. (BH.} - Centella L. p.p. (Umb.). 



Solandra Sw. Solanaceae (3). 6 trop. Am. 



Solanopsis Borner (Solanum p.p.). Solanaceae (2). 2 Am. 



Solanum (Tourn.) L. (incl. Lycopersicum Hill). Solanaceae (2). 1225 

 trop. and temp. .5". Dulcamara L. (bittersweet, nightshade) and S. 

 nigrum L. in Brit. The fls. are small, with a cone of anthers opening 

 at the tip as in Borago. S. tuberosum L. (S. Am.) is the potato. 

 From the axils of the lowest 1. there spring branches which grow 

 horiz. underground and swell up at the ends into tubers (potatoes). 

 That these are stem structures is shown by their origin and by their 

 possession of buds the 'eyes.' Each eye is a small bud in the axil 

 of an aborted 1. (repres. by a semicircular rim). When the parent 

 plant dies down in autumn the tubers become detached, and in the 

 next season they form new plants by the development of the eyes, at 

 the expense of the starch and other reserves stored in the tuber. By 

 heaping earth against the stem, so as to cover more of the leaf-axils, 

 more of the axillary shoots are made to become tuber-bearing ; hence 

 the value of ridging potatoes. S. Lycopersicum L. (Am.) is the tomato, 

 cult, for ed. fr. S. Melongena L., the egg-fruit, is cult, in warm 

 countries for ed. fr. 



