.64 STUDIES IN THE VEGETATION OF THE STATE 



leaves, thus passing the winter unharmed. The perfect 

 rosette conditions explains the appearance of the clusters of 

 white flowers during the last week of April. Dissemination 

 is secured through animal agency, by virtue of the color and 

 taste of the fruit. lAthospermum canescens is sparsely dis- 

 tributed over the entire prairie, most abundantly, however, 

 in low prairies, where it averages one or two individuals per 

 quadrat. The throat of its hypocrateriform corolla is par- 

 tially closed by projecting folds or sinuses. The nectar-bear- 

 ing flowers are heterodistylous, the stamens and stigmas being 

 separated by nearly the length of the corolla tube, xenogamy 

 always resulting. A visiting insect carries pollen from the 

 high stamens of one plant to the high stigma of another, and 

 from the low stamens to the low stigmas. Dioecism practic- 

 ally obtains, with the advantage that no plant is unfruitful. 

 LitJwspermum angustifolium has about the same distribu- 

 tion as the above species, but it occurs only now and then, and 

 is a rare plant in the formation. In L. angustifolium the tube 

 of the nectariferous corolla is much elongated, at least in 

 earlier flowers, and its throat is entirely closed with the prom- 

 inent appendages. The pollen is thus well protected from 

 insect enemies and excessive moisture. Allogamy results, 

 but the means ai'e not clear. The later cleistogamous flowers 

 of this species are much more fertile than the earlier chasmo- 

 gamous ones. These two species, even with sparse numbers, 

 brighten the prairie with their shades of yellow and give a de- 

 cided tone to the aspect. Of the two plants, L. canescens is 

 the more conspicuous on account of its bright colors and its 

 almost leafless, compactly flowered racemes. The flov/ers of 

 L. canescens are also very fragrant. Both of the puccoons 

 are perennial by deep, thick roots, from which the stems 

 sprout up very early in the spring. Plants of L. angusti- 

 folium frequently pass the winter in the rosette condition. 



The most striking plant of the vernal aspect is Baptisia 

 hracteata, which begins blossoming during the first week in 

 May and continues for about twenty days. Itsmassiveracemes 



