79. Cactaceae 161 



5. Lythruni L. Loosestrife 



1. Flowers large, 12-15 mm in diameter, whorled in terminal spicate 

 panicles; leaves opposite or whorled; stamens twice as many as 

 the petals; swamps and wet meadows, occasional; nat. from 

 Eur. June-Aug. Purple Loosestrife L. salicaria L. 



1. Flowers small, 6-10 mm in diameter, solitary, axillary; leaves 

 mostly alternate; stamens and petals 5-7; meadows and road- 

 sides, common throughout 111. June-Aug. Clommon Loosestrife 

 -L. a la turn Pursh 



6. Cuphea P.Br. — Waxweed 



C. pctiolata (L.) Koehne. Dry soil througliout HI., except the 

 extreme northern counties. July-Oct. [C. inscosissima Jacc|.; Parsonsia 

 pctiolata (L.) Rusby]. 



76. Thynielaeaceae CI.F.Meiss. — Mezereum Family 



1. Dirca L. — Leathei~wood 



D. palustris L. Woods and thickets, local. Apr. -May. 



77. Elaeagnaceae Lindl. — Oleaster Family 



1. Leaves opposite; stamens 8 1. Shepherdia 



I. Leaves alternate; stamens 4 2. Elaeagnus 



1. Shepherdia Nult. — Canadian I3ufTalo-berry 

 S. canadensis (L.) Nutt. Dry bluffs and banks or ravines near L. 

 Michigan; Lake Forest, Lake Co., E. /. Hill in 1904; Glencoe, Cook 

 Co., G. D. Fuller in 1943. 



2. Elaeagnus L. — Russian Olive 



E. angustijolia L. Cultivated, and sometimes escaped; introd. from 

 Eur. 



78. Passifloraceae Dumort. — Passion-flower Family 



1. Passiflora lu. — Passion-flower 

 1. Leaves deeply ,'i- to 5-lobed. the lobes serrate; flowers subtended 

 by a conspicuous involucre of 3 bracts; petals la\ender or 

 whitish; berry 5-7 cm long, yellow; dry soil, s. 111. May-July 



- P. incarnata L. 



1. Leaves obtusely 3-lobed above the middle, the lobes entire; flowers 

 without an in\-olucre; petals greenish-yellow; berry about 1 cm 

 long, purple; thickets, s. 111., extending northward to Pike, 

 and Vermilion counties. May-July. [P. lutca var. glabriftora 

 Fern.] P. lutca L. 



79. Cactaceae Lindl. — Cactus Family 



1. Opuntia Mill. - Prickly-pear 

 O. rafinesquii Engelm. Sandy soil, locally abundant; chiefly in the 



