1894. ] Briefer Articles. 41 
gradually approached forming a perfect imitation of the shell of some 
lamellibranch. I found upon observation that the longitudinal bars 
on the sheets were due to slight inequalities in the thickness, caused 
by corresponding inequalities in the size of the riftin thestem. Dur- 
ing the process of crystalization of the water at the surface of the cam- 
bium layer its expansion caused it to be expressed outward or verti- 
cally to the plant since this was the direction of least resistance to the 
forming ice foil. The forming crystal passing through the rift would 
be moulded into a fashion, so far as the thickness is concerned, corre- 
sponding to the inequalities of the rift. During the first stages of the 
crystalization frequently portions of the dead epidermis or periderm 
would be included, and as the foil extended outward considerable 
portions of the dead outer part of the stem would be carried out upon 
the terminal portion. 
Although familiar with the frost freaks of Helianthemum Canadense 
from the statements in manuals, I had never seen them, and this phe- 
nomenon on the stems of Cunila Mariana seemed to me to be of some 
interest which would possibly justify some extended notice of it to- 
gether with colored illustrations. Accordingly I engaged an artist 
friend to color in oil one of the most beautiful of the specimens. 
Since the frost work could not be taken in doors without fatal results 
to its form and beauty, and it would be rather chilly working at an 
easel in the frosty air of a cold morning, the object was placed just 
outside the window while the artist sat within. A very good picture 
was the result but further consideration of the subject led me to be- 
lieve that the phenomenon was of such common occurrence through- 
out nature it was not worthy of the very dignified treatment which I 
had in mind at the start. So the matter dropped so far as I was con- 
cerned and this interesting phenomenon waited seven long years to be 
recorded, | 
Several mornings during that and following winters the frost 
marvels were observed, and each time also there occurred the well 
known phenomenon of the formation of ice columns in moist soil, 
where the crystallization of the surface moisture causes the forming 
crystal to expand vertically to the earth since that is the direction of 
the least resistance. Capillarity of the soil provides the constant sup- 
Ply from below where the soil is not frozen, and columns are pushed 
UP several inches in height, carrying upon their summits portions of 
the surface soil and refuse matter in the way of leaves, etc. Warm or 
ie days and frosty nights, when the ground is not already frozen, 
or both the formation of the ice columns in moist places on the 
Sround, and the frost wings on the stems of the dittany. The peren- 
