The Gametophyte and Embryo of Botrychium simplex, 
Hitchcock. 
BY 
DOUGLAS H. CAMPBELL. 
With Plate XVI and ten Figures in the Text. 
OTRYCH1UM SIMPLEX, Hitchcock, is the smallest species of the 
genus, and is reported from various stations in northern Europe, Japan, 
and North America, 1 being decidedly a boreal species. In some of its forms 
it shows a striking superficial resemblance to a small Opkioglossum , while 
the larger forms are much like B. lunaria , to which it is undoubtedly not 
very remotely related. There seems to be no doubt, however, that it is 
a valid species. 
Luerssen 2 figures a very interesting series of forms, but thinks that 
these represent, to a great extent, only different ages. The second leaf of 
the young sporophyte, although very small, nevertheless is fertile, and it is 
probably several years before the sporophylls reach their full development. 
Text-fig. i shows two extremes found by the writer in a number of 
specimens collected by Dr. H. C. Lyon, to whom the writer is indebted 
not only for these specimens, but also for the material of the gametophyte 
and young sporophytes upon which the present paper is based. 
Dr. Lyon has sent the writer the following account of the conditions 
under which the material was collected in Minnesota: 
‘ My material of Botrychium obliquum and of B. simplex was collected 
in swampy ground on the shores of Echo Lake. This is a small lake a few 
miles from White Bear Lake. The soil in this district is mostly sand and 
carries a sparse forest of white oak, bur oak, red oak, black oak, birch and 
poplar. All three species of Osmunda occurred here in great abundance. 
Lycopodium obscurum and L . inundatum occur here, while the only known 
station of Opkioglossum vulgatum in this state is at this point. I collected 
Botrychium matricariae folium gametophytes only a few rods from the point 
where those of B. simplex were found. Isoetes occurs abundantly in the 
shallow water of Echo Lake. You will note from the above that this region 
1 Christensen, C. : Index Filicum, 1906. 
2 Luerssen, C. : Die Farnpflanzen oder Gefasskryptogamen, Fig. 181, Leipzig, 1889. 
[Annals of Botany, Vol. XXXVI. No. CXLIV. October, 1922.] 
