190 MORNING-GLORY FAMILY 



small, greenish white or purplish. Horns slender, exserted 

 from the hoods. Pod smooth, glabrous. 



The Narrow-leaf Milkweed is a foothill species, but has 

 been found as far up as Mirror Lake. It is much dreaded by 

 sheepmen on hot days when they are obliged to drive their 

 flocks over dry districts where there is little other vegetation 

 and no water. Under these conditions the sheep are tempted 

 to eat the milkweed, which contains an active poison and 

 causes many deaths. This is sometimes prevented by cutting 

 the' plants down a few days before the sheep are driven 

 through, the object being to dry the herbage and so render it 

 less tempting. 



CONVOLVULACEAE. Morning-glory Family. 

 Chiefly trailing or twining herbs, with alternate leaves or 

 leafless. Flowers regular. Stamens 5, on the corolla-tube 

 and alternating with its 5 lobes. Ovary 2-celled, becoming a 

 globose 2 to 6-seeded capsule. 



Leafy plants with conspicuous flowers 1. Convolvulus. 



Leafless twining herb with small flowers 2. Cuscuta. 



1. CONVOLVULUS. Morning-glory. 



1. C. villosus Gray. Leaves petioled, triangular or heart- 

 shaped, 1 to 2J/2 in. across, velvety with a dense white pu- 

 bescence. Flowers pediceled, from the leaf-axils, the calyx 

 with a pair of broad bracts at base. Corolla creamy white, 

 funnel form, 1 to \y 2 in. long, not lobed. (C malacophyllus 

 Greene.) 



The trailing, leafy stems of this plant are commonly l / 2 to 

 2 ft. long, and may be seen in open pine forests at middle 

 altitudes. 



2. CUSCUTA. Dodder. Love-vine. 



1. C. californica Choisy. Stems twining, pale, leafless. 

 Flowers in loose clusters, very small. Corolla nearly globose, 

 with 5 slender acute lobes. 



The thread-like, orange-colored stems of this dodder en- 

 twine themselves about grasses and other low plants, upon 

 which they are parasitic, although the seeds germinate in the 

 ground. It is abundant in low valleys. Other species are 

 doubtless present but not yet detected. 



POLEMONIACEAE. Gilia Family. 

 Herbs and low shrubs with mostly regular flowers. Calyx 

 and corolla 5-lobed. Stamens 5, inserted on the tube or throat. 



