172 
PROCEEDINGS OP THE ACADEMY OP 
spriag of 1857, I examined damp forests in the neighborhood of Wilmington, 
J^orth Carolina, and Charleston, South Carolina, without detecting it. In Au- 
gust, of 1857, while seeking salamanders and helices, in company with Dr. "Wil- 
son and Mr. Conrad, on the summit of Broad Top Mountain, of the Alleghany 
range, in western Pennsylvania, I found one specimen. Last mouth, while on 
a visit to our fellow member, Mr, S. Powel, at Newport, R. I., one damp morn- 
ing I observed two fine specimens of the planaria, creeping near the top of a 
fence 8 feet in height. On the night of the same day, at the proposal of Mr. 
Powel, by the light of a lantern, we sought for the animal about the fence sur- 
rounding his grounds, and in the course of an hour we found twelve fine speci- 
mens. They were obtained from all parts of the fence, some on the top, and 
others on the ground. 
Eight of them I have preserved alive, and now have them at my residence, 
living in a glass box beneath some fragments of moist wood. Occasionally I 
feed them on a crushed house-fly, which they appear to enjoy, as they suck at 
it with their protruded oesophagus for an hour at a time. 
They are from 5 to 7 lines long, and creep about like the slug, with their snout- 
like head erect. They are light-ash colored, with a blackish streak down each 
side of the back, and a blackish spot just back of the middle, corresponding in 
position below with the mouth. In form they are like an awl split in its length, 
the narrower end forming the head. At the base of the latter is a pair of pro- 
minent black eyes. The lateral borders of the head are often inflected, and the 
head itself is sometimes, in a state of rest, doubled upon the back. The intestine 
presents the same dendritic arrangement as in the true fluviatile planariae. 
Dr. Meigs made some remarks touching the importance of obtaining statistics 
regarding the actual condition of Craniological collections, with a view to esta- 
blish a system of exchanges. 
August ^Ist. 
Vice-President Bridges in the Chair. 
Twenty-seven members present. 
The following paper was ordered to be printed in the Proceedings : 
Mineralogical Notes. 
BY W. J. TAYLOR. 
Lecontite. 
This new and interesting mineral is remarkable as being a double sulphate 
of ammonia and soda with potash, containing two equivalents of water, and 
yet homceomorphous with the group of the anhydrous sulphates, and with 
Mascagnine, which contains but one equivalent of water. According 
to Prof. Dana (System. Mineralogy, p. 379), the formula for Mascagnine is 
RO, SO3 2 HO, but this is a typographical error ; the proper formula for this 
mineral being RO, SO3 + HO, as will be seen in Sixth Supplement to Mineralo- 
gy by Prof. Dana. Lecontite and Mascagnine are consequently homceomor- 
phous, its difference in angle being about four degrees, (Lecontite, /: /= 103° 
12^, 0:11+ 117° 7/ ; Mascagnine, /: J=107° 40^ 0 : H 122° 56^,) and yet 
the one contains two equivalents of water and the other but one. Prof. 
Dana has very kindly made the annexed measurements of two crystals, which I 
sent to him soon after receiving the mineral from Dr. Le Conte, which measure- 
ments I made the substance of a verbal communication to the Academy, on the 
evening of the 16th of February, but owing to a mistake, it did not appear in 
print (though it is recorded in the minutes of that meeting) before the 
May number of the Academy's Proceedings. It was at this time supposed to be 
a new mineral, from the difl'erence in angle found by Prof. Dana between it and 
other homoeomorphous sulphates ; and by a qualitative analysis that I made^ 
[Aug. 
