180 NATURAL HISTORY OF PLANTS. 



treatment of verminal affections. F. atrox ' is one of tlie plants 

 from which the Indians of Rio-Negro prepare the curara, and the 

 juice of F. doliaria,^ which derives its name from the employment of 

 its light wood for the fabrication of large vases for domestic use, is 

 also considered very acrid. The juice of F. radula^ is also a vermi- 

 fuge and rich in caoutchouc, as likewise that of F. vermifugal' F. 

 gummifera, prinoides and elliptica K. are also reported as caoutchouc 

 species in Columbia. Gum lac is a product of several Figs. Its 

 formation is attributed to the Coccus Lacca, a hemipterous insect, 

 the females of which, living in great numbers on the branches of 

 the Ficus indica and religiosa^ produce thereon a sort of continuous 

 crust from the resinous matter which exudes from their bodies. 

 Imbedded in this reddish matter are found, not only the dead bodies 

 of the females, but also eggs which, later on, are hatched and give 

 birth to insects before the issue of which it is preferable to collect 

 the lac.® This latter, formed into sticks, grains, or plates, is used 

 in India for dyeing stuffs. When burnt it emits an agreeable odour, 

 and colours the saliva when it has been masticated for some time. 

 It is used to make varnish for fine cabinet work, and is especially 

 prized among us for bead-work, for making sealing-wax and for 

 the construction of some physical instruments. In medicine, it is 

 employed as a tonic, as an astringent, and forms a constituent of 

 several medicinal dentrifices. 



Contrayerva,'' belonging also to this family, consists of evergreen 

 herbs and derives its name from the property attributed to it in 

 central America as an antidote to the bite of venomous snakes. 

 Dkake root, brought from Peru by the celebrated navigator of that 

 name at the end of the 16 th century, and described by Clusius in 

 1605,* was a blackish rhizome, clothed with adventitious roots and 

 leaf-scars, attributed to Dorstenia Houstoni? LiNNiEus thought that 



1 Mart. Herb. — Urostigma (?) atrox Miq. Arcalu Eheed. Rort. Malab. i. t. 27 {Figuier- 



loc, cit. 105. pagode, F. des Pagodes, Bangan, Pippat, Aswat, 



' Makt. Mat. Med. Brai. 88. — F. Gamelleira Bogaha, Kai). 



K. Ind. Sem. Sort. Berol. {\M6), IS.— TTrostigma « Mek. et Del. Diet. Mat. MSd. ii. 333.— 



doliarium Mia. he. cit. 82 ; Sook. Lond. Journ. Lindl. Fl. Med. 297.— Guib. Srog. Simpl. ed. 



vi. 527 {Gfamelleira, Figueira Branca), 6, ii. 319. 



» F. anthebninthioa Eich. (not Mart.).— 7 Gomez, Be Contrayerva {Mem. Ae. Lisb. 



Fharmacosycea Zadula Mia. loo. eit. 84, t. 26, 1803).— Mer. et Del. Diet. Mat. Med. ii. 672. 



fig. 1 ; Eook. Journ. yn. 64, t. 2, figB. —Guib. op. cit. ii. 315, fig. 434, 435. 



* Mart. Herb. — Pharmacosycea vermifuga s ;Exot. lib. iv. cap. 10. 



Mi«. Uc. cit. 87, n. 6. s L. Spec. ed. 4, 176 ; Mat. Med. 63.— Mill. 



' L. Spec. 1514.— W. Spec. iv. 1134.— Roxb. Diet. iii. 86, n. 3.— Plenck, le. PI. Med. ii. 



;. /«rf. iii. 547.— Lindl. Fl. Med. 298.— Z7io- 8, t. 103. Var. (f) oi D. Contnyerva. 

 tigma nligiomm Gasp. Sic. 82, t. 7, fig. 15. — 



