White and Greenish 



age! For these the perennial wild potato vine keeps open house 

 far later in the day than its annual relatives. Professor Robertson 

 says it is dependent mainly upon two bees, Entecbnia taurea and 

 Xenoglossa ipomoeae, the latter its namesake. 



One has to dig deep to find the huge, fleshy, potato-like root 

 from which the vine derived its name of man-of-the-earth. Such 

 a storehouse of juices is surely necessary in the dry soil where 

 the wild potato lives. 



Happily, the common Momihg-glory {I. purpurea)— Aihs Om^ 

 vohnilus major of seedsmen's catalogues — has so commonly es> 

 caped from cultivation in the eastern half of the United States 

 and Canada as now to deserve counting among our wild flowers, 

 albeit South America is its true home. Surely no description of 

 this commonest of all garden climbers is needed; every one has 

 an opportunity to watch how the bees cross-fertilize it 



The vine has a special interest because of Darwin's illuminat- 

 ing experiments upon it when he planted six self-fertilized seeds 

 and six seeds fertihzed with the pollen brought from flowers on a 

 different vine, on opposite sides of the same pot. Vines produced 

 by the former reached an average height of five feet four inches, 

 whereas the cross-pollenized seed sent its stems up two feet 

 higher, and produced very many more flowers. If so marked a 

 benefit from imported pollen may be observed in a single genera- 

 tion, is it any wonder that ambitious plants employ every sort of 

 ingenious device to compel insects to bring them pollen from dis- 

 tant flowers of the same species ? How punctually the Moon- 

 flower (/. grandiflora), next of kin to the morning-glory, opens its 

 immense, pure white, sweet-scented flowers at night to attract 

 night-flying moths, because their long tongues, which only can 

 drain the nectar, mav not be withdrawn until they are dusted 

 with vitalizing powder for export to some waiting sister. 



Cronovius' or Common Dodder; Strangle- 

 weed; Love Vine; Angel's Hair 



{Cuscuta Qronovii) Dodder family 



Flowers — Dull white, minute, numerous, in dense clusters. Calyx 

 inferior, greenish white, 5-parted; corolla bell-shaped, the 5 

 lobes spreading, 5 fringed scales within ; 5 stamens, each in- 

 serted on corolla throat above a scale ; 2 slender styles. Stem : 

 Bright orange yellow, thread-like, twining high, leafless. 



Preferred Habitat— mQ\%\ soil, meadows, ditches, beside streams. 



Flowering Season — July — ^September. 



OistribuUon — ^Nova Scotia and Manitoba, south to the Gulf States. 



246 



