320 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



3. Platanus wrightii S. Wats. Proc. Amer. Acad. 10: 349. 1875. 



Northern Chihuahua and Sonora ; sometimes planted as a shade tree. South- 

 ern Arizona (type locality) and New Mexico. 



Tree with broad crown, sometimes 24 meters high, with a trunk diameter of 

 1.5 meters, the bark brownish, scaling off in thin sheets; leaves 15 to 20 cm, 

 wide, with 3 to 7 long narrow lobes, these entire or sparsely dentate ; wood light 

 brown, its specific gravity about 0.47. 



4. Platanus racemosa Nutt. N. Amer. Sylv. 1 : 47. 1842. ; ^t 

 Baja California. California (type locality). 



Large tree, sometimes 38 meters high, with a trunk diameter of 2.7 meters; 

 leaves deeply lobed, 15 to 25 cm. wide; wood hard, coarse-grained, light brown, 

 weak and not durable, its specific gravity about 0.49. 



5. Platanus chiapensis Standi. Contr. U. S. Nat. Herb. 20: 212. 1919. 

 Chiapas ; type from ZincantS,n. 



Tree, 15 meters high ; leaves with 3 short acute lobes, or merely coai^sely and 

 remotely dentate, 9 to 23 cm. long, fulvous-tomentose beneath. 



6. Platanus lindeniana Mart. & Gal. Bull. Acad. Brux. 10 ': 342. 1843. 

 Veracruz and Puebla to Chiapas ; type from Jalapa. 



Tree, 30 to 40 meters high ; leaves 9 to 20 cm. long or larger, with 3 long nar- 

 row lobes. "Alamo" (Veracruz). 



This may be the species reported from Uruapam by Sess4 and Mocino * as P. 

 orientalis. That name belongs to an Old World species. 



7. Platanus oaxacana Standi. Contr. U. S. Nat. Herb. 20 : 213. 1919. 



Known only from the type locality, San Miguel Alborrados, Oaxaca, altitude 

 1,950 meters. 



Leaves 12 to 20 cm. wide. 



59. CROSSOSOMATACEAE. Crossosoma Family. 



Reference: Small, N. Amer. Fl. 22:231-232. 1908. 



1. CROSSOSOMA Nutt. Journ. Acad. Phila. II. 1:150. 1848. 

 Shrubs or small trees with rough astringent bark; leaves alternate, thick, 

 small, entire ; flowers perfect, solitary, white or purplish ; sepals and petals 5 

 each ; stamens usually 15 or more ; fruit a cluster of 2 to 5 follicles. 

 Petals broadly obovate or orbicular-obovate ; follicles many-seeded. 



1. C. calif omicum. 

 Petals spatulate or oblong; follicles few-seeded. 



Body of the follicle oblong-cylindric, rugose 2. C. big'elovii. . 



Body of the follicle ovoid, reticulate 3. C. parviflorum.. 



1. Crossosoma calif omicum Nutt. Journ. Acad. Phila. II. 1:150. 1848. 

 Guadalupe Island, Baja California. Islands off the coast of southern Cali- 

 fornia ; type from Santa Catalina Island. 



Shrub or small tree with rough scaly bark ; leaves oblong, obovate, or spatu- 

 late, 2.5 to 9 cm. long, sessile or nearly so ; petals white, 1.5 to 1.8 cm. long. 



2. Crossosoma bigelovii * S. Wats. Proc. Amer. Acad. 1 1 : 122. 1876. 



' PI. Nov. Hisp. 163. 1887. j 



* John Milton Bigelow (1804-1878) was appointed in 1850 surgeon of the Mexi- ' 

 can Boundary Commission, and in 1853 surgeon and botanist of the exi>edition 

 under Lieutenant Whipple, which explored the route for a railroad along the 

 thirty-fifth parallel. He made large collections of plants, which were reported I 

 upon by Torrey and Gray. 



