PART 3, 1911] RUTACEAE 211 



2-celled (rarely 3-celled), tardily dehiscent, tough, nut-like capsule, more or less distinctly 

 margined, the valves concavo-convex, the body not reticulate, but roughened by numerous 

 tuberculate glands. 



Type species Ptelea aptera Parry. 



1. Taravalia aptera (Parry) Greene, Leaflets 1 : 222. 1906. 



Ptelea aptera Parry, Proc. Davenp. Acad. 4: 39. 1884. 

 Ptelea nucifera Greene, Contr. U. S. Nat. Herb. 10 : 75. 1906. 

 Ptelea obscura Greene, Contr. U. S. Nat. Herb. 10 : 76. 1906. 

 Taravalia obscura Greene, Leaflets 1 : 223. 1906. 

 Taravalia nucifera Greene, Leaflets 1 : 223. 1906. 



A low, slender or much branched shrub, sometimes attaining a height of 5 m. with 

 dark-brown tuberculate twigs, hispidulous at least when young with appressed hairs ; 

 leaflets variable in size and shape ; lateral leaflets narrowly to broadly elliptic or somewhat 

 obovate, 0.6-3 cm. long, the terminal one narrowly obovate to obovate or rhombic-ovate, 

 1.5-3.8 cm. long, acute, obtuse, or emarginate at the apex, cuueate to obliquely rounded at 

 the base, inequilateral or equilateral, hispidulous on both surfaces or nearly glabrous, the 

 margin crenulate and more or less revolute ; staminate flowers : sepals ovate, hispidulous ; 

 petals oblong to oblong-lanceolate, elliptic or broadly elliptic, 5-6 mm. long ; fruit elliptic 

 to round-ovate or oval, 0,8-2 cm. long, subcordate or truncate at the base, sometimes emar- 

 ginate at the apex. 



Type locality : Dry hill-slopes near sea at Punta Banda, southern end of Todos Santos Bay, 

 Lower California. 



Distribution : Lower California. 



Illustration: Garden & Forest 3: iii,f. 45. 



17. THAMNOSMA Torr. & Frem. in Frem. Rep. 313. 1845. 



Rutosma A. Gray, Gen. 111. 2 : 143. 1849. 



Strong-scented glandular shrubs or partially herbaceous undershrubs. Leaves simple, 

 alternate, entire, linear, sometimes reduced to scales. Flowers perfect, in racemes or race- 

 mose cymes. Sepals 4. Petals 4, imbricate in the bud, erect or barely spreading in anthesis. 

 Disk cup-like, entire or crenate. Stamens 8, inserted on the disk, filaments subulate or fili- 

 form. Ovary 2-celled or rarely 3-celled, 2-lobed, long-stalked or nearly sessile ; style filiform ; 

 stigma capitate ; ovules 5 or 6 in each cavity. Capsule leathery, 2-celled, 2-lobed, opening 

 at the apex. Seeds 4-6, reniform or cochleate-reniform. Testa crustaceous, smooth or 

 rough. Embryo curved. 



Type species, Thwmnosma montana Torr. & Frem. 



Petals 3-5 ram. long, 2-3 mm. broad ; capsule sessile or very short-stipitate ; seeds 



1.5-2 mm. long, tuberculate. 1. T. texana. 



Petals 8-14 mm. long, 4-5 mm. broad ; capsule distinctly stipitate ; seeds 4-6 mm. 

 long, smooth. 2. T. montana. 



1. Thamnosma texana (A. Gray) Torr. Bot. Mex. Bound. 

 Stirv. 42. 1859. 

 Rutosma texana A. Gray, Gen. 111. 2 : 144. 1849. 



A low partially herbaceous undershrub, 1-5 dm. tall, with slender, erect or spreading 

 stems; leaves linear-oblong or filiform-linear, 5-15 mm. long, entire, sessile; flowers in 

 terminal, interrupted racemes; sepals ovate to oval, obtuse or retuse, somewhat unequal; 

 petals oval or elliptic, 3-5 mm. long, 2-3 mm. broad, greenish-yellow or whitish, often tinged 

 with purple ; stamens shorter than the petals ; filaments subulate ; anthers oval or round, 

 apiculate ; ovary sessile ; style not exserted ; capsule coriaceous, sessile or ver.v short- 

 stipitate, lobed nearly to the middle, 3-7 mm. high; seeds reniform, flattened, tuber- 

 culate, 1.5-2 mm. long ; embryo curved ; cotyledons linear. 



Type locality : Western Texas. 



Distribution: Colorado to Texas, Arizona, and northern Mexico. 



Illustration: A. Gray, Gen. IU. pi. 155. 



