FAMILIES OF PLANTS 
61 
Batrachium grayanum is another species that has been reported as 
occurring in the park. 
The genus is commonly called water crowfoot. 
Thaliotrum occidentale.— From 2 to 4 feet high and with only 
2 or 3 leaves which are 2 to 4 times compound and have 
numerous, small, rounded leaflets. The greenish flowers are imper¬ 
fect with the staminate flowers on different plants from the pistillate. 
The stamens are numerous while the pistils are several, but usually 
only a few of them mature. 
Thaliotrum sparsiflorum differs in having perfect flowers. 
Thaliotrum megacarpum and T. dioicum have also been reported 
in the park. 
Actaea arguta. —This plant has a single, large, basal compound 
leaf which is long-petioled and each of its three divisions is 
long-stalked and pinnate. The leaflets are ovate and 2 to 5 inches 
785717°—48-5 
Batrachium ftacddum. —Wholly submersed in the water of ponds 
and streams except that the flowers are at the surface. The leaves 
are alternate and very finely dissected, and they are so delicate that 
they collapse when they are withdrawn from the water. The flow¬ 
ers are solitary on long stalks opposite the leaves. The petals are 
white but yellowish at the base, and the stamens and pistils are 
numerous. 
Batrachium confervoides differs in having a very slender, hairlike 
stem and much smaller flowers, 
each with only 5 to 12 stamens. 
Figure 44.—Meadowrue. Greenish. Pho¬ 
tograph by A. R. Sweetser. 
Figure 45. — Marshmarigold. Creamy 
white. Photograph by Joseph S. Dixon, 
National Park Service. 
