97. Primulaceae 179 



97. Primulaceae Vent. — Primrose Family 

 1. Lobes of the calyx and corolla erect or spreading, not reflexed. 

 2. Plants small, scapose, acaulescent, terrestrial. 



3. Corolla-tube equalling or exceeding the calyx: plants perennial 



1. Primula 



3. Corolla-tube shorter than the calyx; annuals 2. Androsace 



2. Plants with leafy stems. 



4. Plants aquatic; immersed leaves pectinate 3. Hottonia 



4. Plants not aquatic; leaves entire. 



5. Leaves alternate. 



6. Flowers solitary, axillary, sessile; capsule circumscissile 



4. Centunculus 



6. Flowers in axillary racemes; capsules opening by 5 valves 



5. Samolus 



5. Leaves mostly opposite or whorled. 



7. Flowers white; leaves mostly near apex of stem 6. Trientalis 



1 . Flowers yellow or scarlet; stems leafy. 



8. Flowers scarlet (rarely white) ; capsules circumscissile; plants 

 annual 7. Anagallis 



8. Flowers yellow; capsules dehiscent by valves; plants perennial 

 8. Lysimachia 



1. Corolla-lobes reflexed; stamens exserted, connivent, forming a cone; leaves 

 all basal 9. Dodecatheon 



1 . Primula L. — Primrose 

 P. mistas.mnca Michx. Limestone cliffs in Apple River Canyon, Jo 

 Daviess Co. May-Jime. [P. mistassinica \ar. novcboracensis Fern.]. 



2. Androsace L. 



A. occidentalis Piash. Sandy soil, local. April. 



.T. Hottonia L. — American Featherfoil 



H. uiflata Ell. In shallow water, rare; Jackson and Union coimties. 

 June-Aug. 



4. Centunculus L. — Chaffweed 



C. yninimus L. Moist ground, chiefly in the w. and s. coimties. 

 May-Sept. 



5. Samolus L. — Brook weed 



.S". pari'iflorus Raf. Wet soil nearly throughout 111., except the 



northeastern counties. June-Aug. [S. floribundus HBK.; S. '' pauci- 

 florus" Deam] 



6. Trientalis L. — Star-flower 



T. borealis Raf. Woods and thickets, known from Cook, Lake, 

 La Salle, Ogle, and Winnebago counties. Jime-July. [T. americana 

 Pursh]. 



7. Anagallis L. Pimpernel 



A. arvensis L, Waste places, occasional; nat. from Eur. June-Aug. 



