BULLETIN OF THE BUSSEY INSTITUTION. 167 
The stage of development of the plants will appear from the fact that 
their lower spore cases were empty, while the middle ones were full, 
and the upper ones were still closed. A few sterile stems were be- 
ginning to show themselves when this specimen was collected. ‘These 
fertile stems were succulent and tasted like raw beet-tops. The taste 
was not astringent. ‘The juice was slightly acid to test-paper, and 
blackened the fingers when they came in contact with the kuife used 
for cutting the plants, much as the juice of asour apple would do. 
II. Sterile stems of Lguisetum arvense, collected on a railway embank- 
ment, May 22,1876. These stems were from 7 to 9 or 10 inches high. 
Apple-trees were in blossom at the time this specimen was collected. 
The results of the analyses were as follows : — 
Horse-Tail. Green Plants. Dried at 110° C. 
IE Ane I. ay 
Fertile. Sterile. Fertile. Sterile. 
VELL ssh se, «as ee 87.28 85.63 —— —— 
Ash (free from C & COQ, and 
oC a 1.60 1.74 12.55 12.12 
PAADUMNINOLUE oe, «hh es 1.86 8.34 14.62 23.26 
Carbohydrates(including fat) 7.39 6.80 58.11 47.31 
Cellulose (free fromash) . 1.87 2.49 14.72 17.31 
100.00 100.00 100.00 100.00 
Dry organic matter . .. 11.12 12.63 87.45 87.88 
Fat, &c. (ether-extract) . 0.34 0.76 2.68* 5.31* 
Nitrogen . .... ©. -- 0.29-0.30 0.53-0.54 2.34 3.72 
REDHUIGURAIY he icity 6), &m ots» 2.67T 1.99-2.00 21.00 13.90¢ 
Ratio of albuminoids to car- 
bohydrates rss 1:4 a2 1:4 Le2 
Of “silica and sand” together, as obtained by fusing a weighed 
quantity of the crude ash of the sterile stems with carbonate of soda, 
and subsequently separating the silica with an acid in the usual way, 
* The marked difference in the amounts of ether-extract, or “ fat,’”’ found in 
the sterile and in the fertile stems is plainly due to the different amounts of 
chlorophyl contained in the two kinds of stems: the sterile stems, namely, 
with their abundant green branches, are rich in chlorophyl ; while the pale, fer- 
tile stalks contain only a comparatively small proportion of this substance. 
+ The high percentage of crude ash in the fertile stems was due to the pres- 
ence of a number of grains of sands that had been caught up mechanically from 
the sandy soil on which they grew. It was found that 8.11% of such sand was 
contained in the anhydrous matter of the fertile stems. 
t The number 13.90, given in the text, is the mean of two estimations of ash, 
which gave 13.87% and 13.92%, respectively. Other determinations of crude 
ash, made at a later period, gave 13.50 % and 13.55%. The mean of the four 
trials was 13.70 %. 
