158 PROCEEDINGS OF THE AMERICAN ACADEMY. 



RUTACEAE. 

 Zanthoxylum, L. 



Z. Pterota, HBK. Nov. Gen. & Sp. vi. 3 (1823) ; Hook. f. (3), 

 231; Anderss. (1), 244, & (2), 106; Rob. & Greenm. (1), 145 

 (Xanthoxylon). Z. lentiscifolium, Anderss. 11. ec. Fagara Pterota, L. 

 Syst. Nat. ed. 10, 897 (1760) ; Engl. & Prantl, Nat. Pflanzenf. iii. Ab. 

 4, 117. F. lentiscifolia, H. & B. ace. to Willd. Enura. Hort. Berol. 

 165. — Galapagos Ids.: /label. Abingdon Isl. : alt. 525 m., Snod- 

 grass & Heller, no. 836 (hb. Gr.). Albemarle Isl. : Iguana Cove, 

 Snodgrass & Heller, nos. 53 (hb. Gr.), 903 (hb. Gr.) ; mountain east 

 of Tagus Cove, alt. 925 m., Snodgrass & Heller, no. 231 (hb. Gr.). 

 Charles Isl. : Andersson, identity doubtful ; Lee (hb. U. S. Nat. Mus.). 

 Chatham Isl. : southwest end, middle region, Baur, no. 40 (hb. Gr.). 

 James Isl. : Darwin. — Narborough Isl. : southern part, small tree, 

 abundant at 615 m. alt., Snodgrass & Heller, no. 333 (hb. Gr.). 

 Further distrib. S. United States, Mex., "W. Ind., S. Am. 



SIMARUBACEAE. 



Castela, Turp. 



C. galapageia, Hook. f. (3), 229, & (4), 262 ; Rob. & Greenm. (1), 

 145. C. galapageja, Anderss. (1), 243, & (2), 106. C. Galapngei, 

 Engl. & Prautl, Nat. Pflanzenf. iii. Ab. 4, 219. 



This species, like Euphorbia viminea and several other Galapageian 

 plants, shows pronounced formal differences on the different islands, thus : 



Forma typica, inarmata ; folds linearidanceolatis acutis. — Chatham 

 Isl. : Darioin ; Baur ? 



Forma albemarlensis, inarmata vel aculeis parvis gracilibusque 

 armatis ; folds oblongis obtusis mucronatis, 1.5-3.4 cm. longis, saepissime 

 dentibus 1-2 parvis lateralibus instructis, supra haud lucidis. — Albe- 

 marle Isl. ; southern part, Baur, no. 45 (hb. Gr.) ; Tagus Cove, Snod- 

 grass & Heller, nos. 156 (hb. Gr.), 924 (hb. Gr.), the latter showing the 

 hitherto undescribed fruit to be obovoid, 12 mm. long, 9 mm. thick, very 

 smooth and shining. 



Forma bindloensis, inarmata ; folds integerrimis, anguste obovatis, 

 rotundatis vel mucronulatis, 1-1.6 cm. longis, supra haud lucidis. — 

 Bindloe Isl. : Baur, no. 43 (hb. Gr.). 



Forma carolensis, spinis brevibus robustioribus armata ; folds spatu- 

 latis basi maidfeste attenuatis, demum supra valde lucidis 2-2.5 cm. 



