PURSLANE FAMILY 467 



white-scarious margins. 1 to 21/0 lines long, equaling or exceeding the 5 obovate 

 white petals: stamens 5 (or 6 to 8) ; seeds many. 

 Colorado Desert. Apr. -May. 



Locs. — Coachella, Girata; Borrcgo Spr., T. Brnndi nee ; McCoy Wash. EM ,5947; Indio, 

 ace. Parish. 



Refs. — Calandrinia ambigua Howell, Erythea, 1: 34 (1893). Chiytoma ambigua Wats. 

 Proc. Am. Acad. 17: 36.5 (1882), type loc. Kl Bio, Colorado River, Lemmon. Calandrinia 

 nesuvioides Gray, Proc. Am. Acad. 22: 278 (1887). 



3. MONTIA L. Indl\n Lettuce. 



Moderately succulent low herbs, very glabrous and often glaucous. Stems 

 usually clustered. Leaves alternate, opposite, or basal. Flowers white or 

 pinkish, commonly nodding in the bud, usually reopening the second or third 

 day, borne in racemes or clusters, sometimes solitary. Pedicels commonly 

 spreading or recurved in fruit. Sepals 2. persistent. Petals 5, equal or some- 

 what unequal, distinct, or more or less connate at base. Stamens 5 or 3. Style- 

 branches 3. Capsule 3-valved from the apex, 1 to 3- seeded. — About 20 species, 

 chiefly western North America, one species cosmopolitan. (Giuseppe Monti, 

 Italian botanist, died 1760.) 



Our representatives of the genus fall into groups of a few closely related 

 species. The species in a group sometimes differ by slight characters and 

 tend to run together. ^lontia perfoliata is especially variable; wliile its ex- 

 treme variants are sufficiently pronounced for specific rank, such status is pre- 

 cluded l)y numerous intermediate forms. ]\Ioreover occasional plants, fairly 

 typical of the species, show in their development stages similar to the various 

 forms here listed as varieties. All of the species have the pedicels more or less 

 recurving in fruit, save that in Montia sibirica the spreading or deflexed pedi- 

 cels remain straight. 



A. Petals united at base into a tube, not notched at apex. 



Stamens .'1 ; petals unequal; leaves opposite 1. M. fontana. 



B. Petals distinct or a little united, commonly notched at apex. 

 1. Leaves alternate ; petals equal or unequal. 

 Stamens 3; annuals; petals unequal. 



Petals minute ; upper leaves searious-dilated at base L'. M. howellii. 



Petals 2 lines loiii; ; leaves less searious-dilated at base or scarcely at all so 



li. M. linearis. 

 Stamens 5; petals equal. 



Stems diffuse, dicliotomous; annual 4. M. diffusa. 



Flowering stems simple and scape-like; perennial by stolons or bulblets. 5. M. pariifolia. 

 :?. Leaves ba.ml or oppo.'iite ; petals equal; staviens .'). 

 Stems bearing several jiairs of opposite leaves; racemes axillary or terminal; perennial by 



bulblets G. M. chamissoi. 



Stems bearing one pair of leaves, these opposite; racemes terminal. 

 Cauline pair of leaves more or less united; annuals. 



Cauline pair of leaves iniited into a roundish or angular disk; petals conunonly white 

 and usually little surpassing the sepals; rather coarse annual. 7. M. perfoliata. 

 Cauline pair of leaves not forming a disk, partially joined on one side. . 



Stems slender; j)etals commonly pink, 3 times as long as sepals 



8. M. lu/psophiloides. 



Caespitose dwarf; petals white, little exceeding sepals 9. M. spatlmlata. 



Cauline pair of leaves quite distinct. 



Pedicels 1 to 3 lines long; anniijils. 



Plant somewhat diffuse; leaves narrowly linear 10. M. exigua. 



Plant a succulent ball; leaves obovate or spatulate, nearly sessile 



11. M. saj-o.sa. 

 Pedicels % to 2 Indies long. 



Pedicels bracteate ; annuals or perennials. 



Stem from a thick crown or short rootstock ; coast 12. M. sibiri"a. 



