STONECROP FAMILY 331 



short, or often very slender and exceeding the leaves ; sepals usually 4, 1 mm. long, ovate ; petals 

 lanceolate, acuminate, scarcely equaling the sepals ; seeds 1 or rarely 2. 



Dry usually sandy or gravelly places, Sonoran Zones; southern Oregon to Lower California, also Chile. 

 Type locality: Concepcion, Chile. Feb.-May. 



2. TILLAEASTRUM Britt. Bull. N.Y. Bot. Gard. 3: 1. 1903. 



Diminutive aquatic or uliginous, glabrous annuals with opposite leaves and minute 

 flowers solitary in the axils. Sepals usually 4, distinct. Petals as many as sepals, distinct 

 or united at the base. Carpels commonly 4, distinct; styles short. Fruiting carpels few- to 

 several-seeded. [Name Latin, in reference to the close resemblance of these plants to the 

 genus Tillaea.~] 



A genus of about 20 species of wide geographic distribution. Type species, Tillaeastrum aquaticum (L.) 

 Britt. 



1. Tillaeastrum aquaticum (L.) Britt. Water Pigmy-weed. Fig. 2175. 



Tillaea aquatica L. Sp. PI. 128. 1753. 



Buillardia aquatica DC. Prod. 3: 382. 1828. 



Tillaea angustifolia Nutt. ex Torr. & Gray, Fl. N. Amer. 1 : 558. 1840. 



Tillaea Drummondii Torr. & Gray, Fl. N. Amer. 1: 558. 1840. 



Tillaea Bolanderi Greene, Fl. Fran. 183. 1891. 



Crassula aquatica Schoenl. in Engler & Prantl, Nat. Pflanzenf. 3 2a : 37. 1891. 



Tillaeastrum aquaticum Britt. Bull. N.Y. Bot. Gard. 3: 1. 1903. 



Stems 1-8 cm. high, more or less branched, slender, erect or spreading. Leaves linear- 

 oblong, 4-6 mm. long, connate at base ; flowers solitary in the axils on pedicels shorter than or 

 in fruit exceeding the leaves, 4-merous or rarely 3-merous ; sepals about 1.5 mm. long; petals 

 slightly exceeding the sepals, greenish ; carpels longer than the sepals ; seeds several. 



Mud, Transition and Sonoran Zones; widely distributed in the Pacific States, but not common, ranging across 

 the continent; also in Europe and Africa. May- July. River-leek. 



3. SEDELLA Britt. & Rose, Bull. N.Y. Bot. Gard. 3: 45. 1903. 



Diminutive annuals with slender stems, usually few-branched above the base. Leaves 

 small, ovoid-oblong, fleshy. Flowers small, yellow, cymose. Calyx with 5 small triangular 

 teeth. Petals 5, united at the base, linear to ovate-lanceolate. Stamens 5 or 10. Carpels 5, 

 oblong, erect or spreading; styles slender. Seeds solitary in the carpel, erect. [Name 

 diminutive of Sedum.~\ 



A Californian genus of three or four species. Type species, Sedella pumila (Benth.) Britt. & Rose. 



Stamens 5; petals 2 mm. long, erect in both flower and fruit. 1. 5". pentandra. 

 Stamens 10. 



Petals 3-4 mm. long, spreading in flower, erect in fruit; follicles connivent. 2. 5". pumila. 



Petals 2 mm. long, spreading in both flower and fruit; follicles spreading. 3. 5. Congdonii. 



1. Sedella pentandra H. K. Sharsmith. Mount Hamilton Sedella. Fig. 2176. 



Sedella pentandra H. K. Sharsmith, Madrono 3: 240. pi. 12. 1936. 



Erect glabrous annual, 3-10 cm. high, the stem straight, simple up to the inflorescence or 

 with a few virgate branches from lower nodes. Lowest leaves opposite.^ the others alternate, 

 closely imbricate in young plants, early deciduous, fleshy, oblong-ovoid to elliptic-obovoid, 4^-7 mm. 

 long, sessile ; cymes usually spicate with 2-5 virgate branches 2-3 cm. long ; bracts leaf-like but 

 small; flowers crowded, 3 mm. long; sepals deltoid, 0.5 mm. long; petals united at base; green- 

 ish yellow, with a median reddish line, lanceolate, 2 mm. long ; follicles 1 . 5 mm. long, yellowish 

 or bright red, densely papillate, erect. 



Rocky exposures, Upper Sonoran Zone; Inner Coast Ranges from Lake County to San Benito County, Cali- 

 fornia. Type locality: Arroyo del Puerto, Stanislaus County, California. April-May. 



Sedella leiocarpa H. K. Sharsmith, Madrono 5: 192. 1940. This recently described species is distin- 

 guished from 5. pentandra by the following characters: follicles glabrous, somewhat spreading; petals 3-3.5 mm. 

 long. Known only from the type locality: "Dry, rocky soil in chaparral, 6.5 miles north of Lower Lake, Lake 

 County, California." 



2. Sedella pumila (Benth.) Britt. & Rose. Sierra Sedella. Fig. 2177. 



Sedum pumilum Benth. PI. Hartw. 310. 1849. 



Sedella pumila Britt. & Rose, Bull. N.Y. Bot. Gard. 3: 45. 1903. 



Diminutive annuals, the stems slender, 2-12 cm. high, usually virgately branching. Leaves 

 ovoid-oblong, fleshy, 2-5 mm. long, sessile, subcordate, alternate or the lowest opposite ; flowers 

 in few-forked cymes, sessile or short-pedicellate ; calyx teeth triangular, minute ; petals linear- 

 lanceolate, 3-4 mm. long, greenish yellow ; stamens 10 ; carpels narrowly oblong, smooth on the 

 back and apex, conspicuously ciliate-papillate on the inner suture; styles slender, erect, 1 mm. 

 long ; follicles connivent but not closely appressed, with a fimbriate row of papillae on the suture. 



Rocky places, especially igneous rocks, Upper Sonoran Zone; foothills of the Sierra Nevada from Sutter 

 County to Merced County and the North Coast Ranges in Napa County, California. March-May. 



