28 ERYTHEA. 



connection with its condition. Generally more than one specimen 

 of any particular kind is available while collecting, and it is moat 

 profitahlo to select those that seem to show the peculiarities of the 

 species in the very best manner. But, if only one specimen of a 

 plant unknown to the collector can be seen at the particular time, it 

 is best to take it rather than to risk the chance of happening to find 

 another one later on, even if it does not look like a well-developed 

 plant. It can readily be discarded later if better are found. In the 

 case of crustaceous species, spreading over considerable areas of rock- 

 surface, portions may be removed with the knife, or portions of the 

 rock may be chipped off with the hammer and chisel. If the plant, 

 however, has a distinct and characteristic margin, a portion of this 

 also should be removed as well as a piece from the center. The 

 holdfast, or a characteristic part of it, should be obtained in the case 

 of all species found attached ; and in the case of species not found 

 attached, careful search should be made to discover specimens with 

 the holdfast still cm them. Some species, of course, do not grow 

 attached, and consequently have no holdfasts. This should not be 

 taken for granted, however. When the plant is of reasonable size, 

 whole plants should be taken for herbarium specimens; but when 

 plants are too large for this, characteristic portions should be taken, 

 including usually the holdfast and adjacent portion, the tip, and of 

 the middle enough to show method of branching and characteristic 

 fruiting organs if they be present. Fruiting specimens of all larger 

 kinds in which the fruit is of fairly large size, enough so at least to 

 be readily seen with the naked eye or with the pocket lens, should 

 be selected in preference to sterile specimens; or if the fruit is 

 unknown to the collector, large and as promising specimens as 

 possible are to be selected, in the hope that microscopic examination 

 will show them present. Specimens covered with diatoms or other 

 parasites or epiphytes, are to be avoided, when others are to be had, 

 uidess they are gathered for the sake of the plants growing on them. 

 The latter may often be, indeed, the more interesting and the rarer 

 of the two. Finally, the specimens taken should be in a good state 

 of preservation. The collector should avoid faded or bleached speci- 

 mens whenever others are to be had. Specimens which show more 

 or less pronounced symptoms of decay, such as the softening of an 

 otherwise firm species, are usually not worth collecting. These 



