THE DEVELOPMENT OP THE FIELD HORSETAIL, igj 



FIG. 2. 



FIG. 



Below it were clustered the smaller buds 

 which were destined to produce the ster- 

 ile parts. 



The stem, reduced to several nodes 

 with merely the suggestion of internodes 

 between, formed the base of the bud. 

 When growth commenced, all the inter- 

 nodes developed at the same time, carry- 

 ing the fruiting cone upward at the rate 

 of an inch and a half, or more, a day. As 

 the stem lengthened, the sheaths grad- 

 ually drew apart forming the leaf-like 

 whorls at the joints. As the cone begins 

 to push out of the bud, its resemblance to a flower is quite striking 



(Fig. 2). 



Investigation seems to prove that the tubers which the plant is 

 reputed to bear occasionally, are much more common than is sup- 

 posed. Nearly all who have studied botany have heard of them, but 

 very few have seen them. A few minutes' work with a shovel at the 

 time the plants are coming up, will give plenty of them. They occur 

 at the joints of both the primary and secondary rootstocks, usually 

 several inches underground, and from their position 

 seem to be in the nature of arrested branches. As 

 many as thirteen tubers have been counted on a single 

 rootstock between the primary rootstock and the fruiting 

 spike. What their office in the economy of the plant is, 

 seems not to have been determined. They may be re- 

 positories for plant food, but if so the fertile stems do 

 not appear to draw very heavily upon them. They are as 

 plump after the fruiting season as before. 



There is a considerable difference in the time of fruit- 

 ing of various colonies, due, apparently, to the soil. They 

 usually start first in dry soil, such as railroad embank- f' 

 ments. Those in wet places are last to mature. One - 

 would naturally think the reverse should be the rule, since 

 other things grow first in the swamps. The water horse- 

 tail {E. fluviatile) produces its earliest stems in wet places, 

 and begins to grow before the field horsetail has started, 

 but the latter comes to maturity much sooner. 



New York, April 27, i8gg. 



