18 BOTANICAL OBSERVATIONS IN WESTERN WYOMING. 
viscosissimum Pursh, Peucedanum leiocarpum Hook., Ligusticum 
scopulorum Gray, Lonicera cerulea L., Aster conspicuus Lindl., 
A. integrifolius Nutt., A. elegans Torr. Gray, A. Engelmanni 
Gray, Senecio triangularis Hook., S. Andinus Nutt., Hieracium 
Scoulerit Hook., Gaultheria myrsinites Hook., Orthocarpus Parryi 
n. sp. Gray (see Appendix, No. 218), Echinospermum deflexum 
Lehm., Spiranthes Romanzoffiana Cham., Fritillaria pudica 
Spreng., Calochortus eurycarpus S. Watson, Botrychium simplex 
Hitcheock. 
At the head of Yellowstone Lake, fringing the muddy shores of 
one of its numerous inlets, was found in great abundance the 
well known European plant, Subularia aquatica L. This has been 
regarded as one of the rarities on the American continent, and 
has been termed by Dr. Gray one of “the late lingerers” which 
has just managed to maintain its foothold in a few isolated New 
England lakes: but it seemed to be quite at home on the banks 
of the Yellowstone. While it is by no means unlikely, as sug- 
gested by Dr. Gray, that from its diminutive size and mode of 
growth, it may have been overlooked in intermediate localities, its 
occurrence here, in such profusion, so remote from any recognized 
connection with an ancestral source, is very suggestive in its bear- 
ing on the question of geographical distribution, and derivative 
origin of species. Certainly the localities on this continent where 
it might have persisted, if originally spread round the northern 
hemisphere, are sufficiently numerous not to leave such wide gaps 
as that between Maine and Wyoming! Doubtless, as in other 
apparently unaccountable cases, future discovery either east or 
west will help to fill up this chasm. 
In the numberless ponds and lagoons which occur near the 
head of Yellowstone Lake only the usual forms of northern aquat- 
ic plants were noticed, including Ranunculus aquatilis L., Nuphar 
advena Ait., Utricularia vulgaris L., Lemna trisulea L., Typha lati- 
olia L., Sparganium simplex Huds., Zannichella palustris L., 
’ Potamogeton perfoliatus L. 
In none of these promising localities was I able to detect the 
Nuphar polysepalum Engel., which seems singularly to affect iso- 
lated localities. 
The various confervoid growths and obscure vegetable organ- 
isms in connection with the numberless hot springs of this region 
will no doubt reward the Special researches of the microscopical 
(178) 
