74 Rhodora [APRIL 
gan. “The monstrosity was an almost regular flower growing on the 
same stem with one of the ordinary form. ... It had no lip but 
three regularly formed pure white petals all of the same size and shape. 
... Here, in a genus affording some of the most strikingly irregu- 
lar flowers in Nature was a flower all but regular." My specimen 
was not such an interesting or so extreme a case of reversion of form, 
but it fits in well with the theories of the development of the orchid. 
As a sidelight on one of Nature's many methods of preventing the 
perpetuation of abnormalities, let me describe a specimen of Arethusa 
bulbosa found in Gloucester in late summer, in 1906. Two faded 
blossoms were growing from a single.root, the only two-flowered 
specimen I ever found. The scapes were parallel and the same 
length, ànd the two flowers faced each other in such a way that the 
parts were interlaced like the fingers of folded hands and the entrance- 
of insects was effectually prevented. "The flowers in fading had stuck 
together firmly, and the shrivelled ovaries showed plainly that fer- 
tilization had not taken place. 
WaABAN, MASSACHUSETTS. 
SOME NOTEWORTHY VARIETIES OF BIDENS. 
M..L. FERNALD. 
In 1908, the writer recorded! the occurrence of the common Euro- 
pean Bidens tripartita L. as an apparently native plant of swamps at 
Percé, Gaspé County, Quebec, and at that time called attention to 
the characters which differentiate it from the American species, B. 
frondosa and B. connata, to which it is related. It was, therefore, 
gratifying, while exploring in August last with Messrs. Bayard Long 
and Harold St. John on the Magdalen Islands in the Gulf of St. 
Lawrence, to find, as we had expected to do, B. tripartita abundant 
there, growing either in shallow water at the margins of brackish 
ponds or in boggy spots near the sea-strand, and later in August to 
' 1 Fernald, Ruopona, X. 200 (1908). 
