228 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



10. Boerhaavia erecta thornberi (Jones) Standley, Contr. U. S. Nat. Herb. 12: 

 381. 1909. 



Boerhaavia thornberi Jones, Contr. West. Bot. 12: 72. 1908. 



Type locality: Tucson, Arizona. 



Range: Arizona and New Mexico and southward. 



New Mexico: Mangas Springs; Guadalupe Canyon. Low hills, in the Upper Sono- 

 ran Zone. 



From B. erecta, which ought to be found in New Mexico, this differs slightly in its 

 more strict habit and not dotted leaves. The leaves of B. erecta are conspicuously 

 dotted beneath. 



46. PHyTOLACCACEAE. Pokeweed Family. 

 1. RIVINA L. 



A low erect branching herb with ovate leaves; flowers small, white or rose-colored, 

 in axillary and terminal racemes; calyx 4-parted; stamens 4 to 8; fruit a reddish 

 berry containing a solitary seed. 



1. Rivina portulaccoides Nutt. Trans. Amer. Phil. Soc. n. ser. 5: 167. 1837. 



Type locality: "On the alluvial lands of the Verdigris river, near its confluence 

 with the Arkansas." 



Range: New Mexico and Arizona to Texas and northern Mexico. 



New Mexico: Guadalupe Canyon (Mearns 683). 



47. AIZOACEAE. Carpetweed Family. 



Fleshy or succulent herbs with usually opposite leaves and no stipules; ovary and 

 capsule 2 to several-celled; stamens and petals sometimes numerous; petals wanting 

 in our genera. 



KEY TO THE GENERA. 



Sepals distinct; leaves scarcely fleshy; stamens 3 to 5; cap- 

 sules 3-celled, many-seeded 1. Mollugo (p. 228). 



Sepals united below; leaves fleshy; stamens 5 to 60; cap- 

 sules 1 to 5-celled. 

 Capsules 3 to 5-celled, many-seeded; leaves linear to 



oblong-lanceolate; stamens 5 to 60 2. Sestjvium (p. 229). 



Capsules 1-celled, with few seeds; leaves round-obo- 



vate; stamens 6 to 10 3. Trianthema (p. 229). 



1. MOLLUGO L. Carpetweed. 



Slender annuals with erect or prostrate much branched stems; leaves linear or nar- 

 rowly oblanceolate, thin; sepals 5, white inside; stamens 5 and alternate with the 

 sepals or 3 and alternate with the 3 cells of the ovary; stigmas 3. 



KEY TO THE SPECIES. 



Cauline leaves linear, glaucous; plants small, less than 10 cm. in 



diameter, erect 1. M. cerviana. 



Cauline leaves narrowly oblanceolate, bright green; plants larger, 



20 to 70 cm. in diameter, prostrate 2. M. verticillata. 



1. Mollugo cerviana (L.) Seringe in DC. Prodr. 1: 392. 1824. 



Pharnaceum cervianum L. Sp. PI. 272. 1753. 



Type locality: "Habitat Rostockii, in Russia, Hispania." 



Range: Texas to California and Mexico; also in the tropics of the Old and New 

 World. 



New Mexico: Mesa west of the Organ Mountains; Filmore Canyon ; Chama River. 

 Dry sandy plains, in the Lower Sonoran Zone. 



