110 
PLANTS OF YELLOWSTONE NATIONAL PARK 
1. Flowers in terminal spikes. 2. 
1. Flowers in axillary racemes. 3. 
2. Flowers violet. Plants alpine. Veronica wormskjoldii. 
2. Flowers pale blue with darker stripes. Plants of wet places. Veronica 
serpyllifolia. 
3. Leaves linear or nearly so. Veronica scutellata. 
3. Leaves oblong or oval. 4. 
4. Fruits 2-lobed. Plants perennial. Veronica americana. 
4. Fruits merely notched at the end. Plants annual. Veronica peregrina . 
Pentstemon or Beardtongue (Pentstemon ).-—Herbs with opposite 
leaves and usually showy flowers. The corolla is irregular and two¬ 
lipped. There are five stamens, but one of them is sterile. It has 
no anther but is usually flattened and bearded at the end, hence the 
name beardtongue. Some species are rather difficult to distin¬ 
guish; those that occur most com¬ 
monly in the park may be identi¬ 
fied by means of the following key. 
1. Flowers dull white or yellowish. 
Pentstemon deustus. 
1. Flowers some shade of blue or 
purple. 2. 
2. Plants smooth throughout. 3. 
2. Plants more or less hairy. 6. 
3. Flowers in dense panicles. 4. 
3. Flowers in headlike whorls. 5. 
4. Flowers large, 1 inch or more long. 
Pentstemon cyaneus. 
4. Flowers smaller, one-half inch or less 
long. Pentstemon cymthus. 
5. Leaves lance-shaped. Pentstemon 
procerus. 
5. Leaves ovate. Pentstemon rydbergii. 
6. Leaves smooth. Pentstemon collinus. 
6. Leaves downy. Pentstemon radtcosus. 
Figure 86. —Pentstemon or Beardtongue. 
Blue. Copyright, J. E. Haynes. 
In addition to the above Pentste¬ 
mon erianthera , P. fremontii , P. 
fruticosus, P. glaber , P. glaucus , 
P. gracilis , P. montanus , P. pseudoprocerus , P. scouleri , P. secundi- 
florus , and P. whippleanus have been reported as occuring in the 
park. 
Little bluelips (Collinsia tenella) is a low, somewhat spreading, 
annual herb, 3 to 6 inches high, with oblong or lance-shaped leaves. 
The lower leaves are opposite and petioled while the upper ones are 
sessile and usually whorled. The flowers are borne in the axils of 
the upper whorls of leaves, 1 to 5 in each whorl. The corolla is blue 
or blue and white and deeply two-lipped. Sometimes called blue¬ 
eyed Mary, 
