280 THE PLANT WORLD. 



the first place it is cumbersome and inconvenient, if not quite im- 

 possible to prepare specimens in this way, and in the second place 

 my success in several trials has not been flattering. My plan 

 now almost invariably is to cut the joints in half with a sharp 

 knife, then remove the greater part of the succulent tissue, after 

 which the specimen is put in press between thin sheets of paper 

 and ordinary driers, like any other plant, except that when 

 possible much more pressure is used. Ordinarily, one can use 

 any amount of pressure from lOO to 300 pounds, and the latter 

 gives more satisfactory results than the former. It is not a 

 pleasant task at all to prepare the specimen for the press. A 

 long, stout-bladed knife is to be preferred, but I use an ordinary 

 jack-knife. The joint is split in two, parallel to the flat sides. 

 Specimens can be dried in this way but it takes a long time. My 

 practice has been to scrape out the pulpy mass, leaving little be- 

 sides the palisade cells attached to the epidermis. The scraping 

 out is usually much more easily done if the vascular reticulation 

 is first removed. If the joint- is an old one, this can be done 

 almost perfectly by cutting the vascular system loose at the con- 

 striction between the joints for a distance of an inch or two or 

 the depth of the knife blade. By holding the epidermal portion 

 flat and bending the vascular bundles back, they may be pulled 

 out complete and much of the pulpy interior will adhere to them. 

 Then by a litte scraping with the knife blade the remainder of the 

 pulpy parenchyma is easily removed, when the specimen is ready 

 for the press. These directions appear formidable, no doubt, but 

 the process is simple enough. 



All who are familiar with the prickly pear will question the 

 comfort of the collector in the preparation of specimens. Of 

 course, the spines and spicules are always present and usually 

 some of them find their way into one's hands, which is very 

 aggravating, especially inasmuch as the hands are usually at 

 the same time slippery and slimy with nnicilage from the plant. 

 But this is one of the penalties of having anything to do with the 

 plants and must be put up with. However, a few precautions 

 and a little care will enable one to minimize the annoyance. 



