146 THE PLANT WORLD. 



Much can be done with a strong pocket lens, but it is best to have a 

 compound microscope with a low power, ranging, perhaps, from 12 to 

 25 diameters. He should also have a pair of slender, fine-pointed 

 tweezers and a couple of dissecting needles, which may be easily made 

 by pushing a strong needle into a slender, soft pine handle. For 

 studying the cellular structure of leaves a number of glass slips and 

 cover glasses, such as are used in mounting microscopical preparations 

 should be at hand. In studying the moss fruit under the microscope 

 it is desirable to view it from all sides, and at all angles. In order to 

 hold it in position, so that an accidental jar or a chance breath may 

 not displace it, press a bit of common beeswax on the center of a glass 

 slip. This should be perhaps 1-16 of an inch in thickness and cover 

 an area half an inch in diameter. With the tweezers the moss fruit 

 and its various parts may be stuck lightly to the wax, and disposed in 

 any position in which it is desired to study them. The glass slip can 

 now be placed under the microscope and the latter tilted at the most 

 convenient angle as regards light. 



We may now assume that the beginner has before him the imple- 

 ments above mentioned, and has provided himself with a "cushion'" of 

 moss which shows a number of well-developed fruits. By gently tear- 

 ing it apart a single plant may be isolated, such as that shown in 

 figures 1 and 2, which is magnified about 10 times in figure 3. It is 

 seen to consist of a slender stem often with several branches, one of 

 which bears the so-called fruit. At the base of ihe stem will be seen 

 a number of fine root- like processes. These are the rhizoids (fig. 3a) 

 which serve mainly to hold it to the substratum on which it grows. 

 The stem is more or less thickly beset with leaves (fig. dh) which are 

 distinct and sessile — that is attached to the stem by their whole base. 

 From the apex of the stem arises the slender, wire-like pedicel (fig. Sc) 

 which bears the capsule or moss fruit (fig. Sd) at its summit. Sur- 

 mounting the capsule is a thin, delicate, scale-like organ known as the 

 calyptra (fig. 4«, 6«), which once formed a covering for the young 

 capsule and was pushed off and borne upon its summit as it reached 

 maturity. The calyptra soon falls, and when the spores are mature, 

 the capsule opens by the separation of the upper portion in the form of 

 a lid or operculum (fig. 7), as it is called. When the operculum is 

 removed there is exposed just inside it a ring of delicate teeth known 

 collectively as the peristoiue (fig. S-:/). Often there is a ring, or rings, 

 of still more delicate teeth inside the outer ring, the first made up of 



