NYCTAGIIVACEAE, the Four-o'Clock Family 



Herbs, with opposite entire leaves and flowers in small clusters 

 surrounded by a broad open calyx-like involucre; the true calyx col- 

 ored like a corolla; petals none (4 8 dm. high; flowers purple, in 

 summer). 



la. Leaves lanceolate or narrower, sessile 



Umbrella-wort, Oxybaphus hirsutus. 

 Ib. Leaves ovate, petioled Umbrella-wort, Oxybaphus nyctagineus. 



ILLECEBRACEAE, the Knotwort Family 



Herbs, with opposite entire leaves, and minute flowers without 

 petals. (Prostrate spreading or freely branched plants, 3 dm. high 

 or less; flowers in summer.) 



la. Stipule's none; leaves slightly connate at base, subulate 



Knawel, Scleranthus anmms. 



Ib. Stipules present, but small; leaves elliptical or oval (Forked 

 Chickweed) 2. 



2a. Stems pubescent; internodes seldom more than 1 cm. long 



Forked Chickweed, Anychia polygxmoides. 

 2b. Stems smooth; internodes about 2 cm. long 



Forked Chickweed, Anychia canadensis. 



AIZOACEAE, the Carpet- weed Family 



Prostrate herbs, with whorled leaves and small whitish axillary 

 flowers without petals, in summer. 



One species in Michigan Carpet-weed, Mollugo verticillata. 



CAKYOPHYLLACEAE, the Pink Family 



Herbs, with opposite or whorled entire leaves, and stems fre- 

 quently swollen at the nodes. Sepals 4 or 5; petals separate, as 

 many as the sepals, or rarely none; stamens twice as many as the 

 petals in plants with conspicuous flowers, sometimes fewer in those 

 with small flowers; ovary 1-celled, with the ovules on a central axis, 

 and with 25 styles. 



la. Calyx spreading, of separate sepals; flowers 15 mm. wide or 



less; petals sometimes none 2. 

 Ib. Calyx tubular, of united sepals; flowers in many species more 



than 15 mm. wide; petals always present 22. 



2a. Stipules present 3. 

 2b. Stipules none 4. 



