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FLOEA or WASHINGTON AND VICINITY. 229 



If several sheets are gummed at one time, which is the best way in 

 order to consume all the mucilage made at once, they may, when dry, 

 be kept in a large book or under some pressure to i) re vent them from 

 rolling up. 



To cut the strips, shears are not to be recommended, although with 

 skill they may be used. The difficulty will be to cut them of a uniform 

 width. It is better to cut them with a shari? knife on a broad piece of 

 pasteboard to a straight-edge. For this latter a thin board, six or eight 

 inches wide and considerably longer than the sheet to be cut, is much 

 more manageable than a narrow rule. The under surface of this board 

 should be rough and the edge smooth. The point of the knife must be 

 kept sharj), and it should have a thin blade. An ordinary shoe-knife is 

 better than a jackknife or penknife. An ink-eraser is a tolerable sub- 

 stitute. The average width of the strips should not be over li lines, 

 but occasionally a wider one will be needed for thick stems. One 

 sheet may be cnt up at a time and when consumed another cut. The long 

 strips thus cut may then be, most of them, cut into short pieces of 

 from half an inch to two inches in length, the ordinary length required 

 being about three-fourths of an inch. A few long strips should be left 

 uncut for special cases as they arise. 



In mounting with gummed strips, the specimens may be deliberately 

 adjusted to the sheets and then fastened down. A wet sponge is needed 

 to moisten the strips which are placed over the stems, peduncles, petioles, 

 etc., wherever they are required to make the plants secure. They should 

 generally be placed over the tips of pointed leaves, and may lie over 

 some flowers without concealing their essential parts. In putting them 

 down, care should be taken to bring the whole of the gummed surface 

 into contact with the paper, except only as much as is occupied by the 

 X)lant, which needs to be tightly encompassed and snugly held down to 

 the sheet. This is best done by a pressure of the thumbnails along 

 both ends of the strip towards, and closely up to the plant. 



As to the relative merits of the two modes of mounting, it may be 

 said that perhaps for very large herbariums, which are in constant use, 

 the method with glue is the best, since the tenderer i^arts of the plants 

 are thus firmly held to the sheets, and not liable to be damaged. 

 This method, however, is not sufficient in cases of terete stems, and 

 needs to be supplemeuted by strips over such parts. The objec- 

 tion to the strip method is that it conceals some parts of the i)lants 

 and makes the sheets look less natural. But if carefully and tastefully 



