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species of the present genus Chorda, Stack. This fragment 
seems to have been mixed in the tide pools with fresh water 
or land plants growing there. For another thick specimen 
of the same locality and compound, bears a profusion of 
marine mollusks, and has only branches of this as yet urn 
described marine species ; Calamophycus septus. 
Habitat Lower Heldeberg Sandstone, Michigan, discovered 
and communicated by Dr. Carl Rominger (State Geologist). 
On comparing my Manx specimen, which was found on 
the surface in a field at Laxey, with that figured and 
described by Prof. Lesquereux; it agrees with the latter in 
every respect, except that striae and scales are not observable 
on the stem. The stem is thick, dichotomous ; divisions 
variable in distance, the terminal ones short, pointed nearly 
equal in size and length, surface nearly smooth. The 
branches in the lower part are thick comparatively to their 
length. The surface of the stem appears to be smooth and 
affords no evidence of striae or scales. 
The wood cut below represents the specimen a little over 
the natural size. 
The stone in which the plant is embedded is a fine 
grained grit of a grey colour, and the specimen itself is of a 
