58 
as before. Continue the process with the potash and acid solu- 
tions alternately until all lumpsarebrokenup. The disintegrated 
material can then be thoroughly washed and further treated in 
the usual manner.” 
Another deposit that is of remarkable interest was struck in 
sinking an artesian well at Cambridge, Maryland, a few months 
since. It contains a number of new and strange forms, but the 
most remarkable is a perfect disc with the raphe and nodules 
of a Navicula. Three species have been observed, two of which 
have a rim closely resembling that of MJelosira sulcata. Spec- 
imens of Tyiceratium, including the curious 7Z7riceratium 
Marylandica, are also pretty abundant. It is to be hoped 
that some of our American workers will figure the new forms of 
this deposit and not wait for the work to be done abroad. We 
hope to have something further to say about it. 
C. HENRY KAIN. 
Forms of Platanus occidentalis. 
I have for many years past pointed out to botanical friends 
the forms of planes of the character indicated at p. 247, Vol. xiii. 
The one with the rounder leaves has them also thin, and of a dull 
green tint. The variety with the more pointed leaves has them also 
coriaceous and with a shining surface. I find the two forms 
together over the whole Atlantic slope, so far as I have seen, 
both in the same localities. Any one can soon learn to distin- 
guish the trees, even when passing them on railroad trains. 
When we collect the specimens and dry them, it is, however, 
very difficult to define the difference. I have several times tried 
to do so with no satisfaction. In regard to variations, gardeners 
find they can be perpetuated by seeds as well as by cuttings. 
In this respect, a variation has not the different behavior from a 
species that at one time was supposed to characterize it. 
THOMAS MEEHAN. 
Euphrasia officinalis, L. 
The note on this plant (Vol. xiii., p. 232) indicates that on 
the northern Atlantic slope its preferences are for rather dry 
situations. It may be of interest to add that in my Alaskan col- 
