Journal of 



Applied Microscopy. 



Volume II. DECEMBER, 1899. Number 12 



On Studying Slime Moulds. 



SECOND PAPER. 



Having in a previous article discussed the study of Myxomycetes in their 

 earlier phases, we pass now to the collection, transportation, and study of the 

 same organisms in fructification or fruit. In some parts of the United States 

 fruit may be obtained at any season of the year. In most localities, however, 

 the best specimens are obtained between May and October. To secure any 

 complete series the student must be in the field almost daily. The plasmodia of 

 some species pass into fruit with great rapidity, and in many cases the fruit is so 

 delicate that the slightest rainfall, or even a strong wind, is sufficient to ruin the 

 beauty of the sporangia, if not destroy them altogether. The student should go 

 forth provided with a strong knife and pasteboard boxes, large and small, m 

 sufficient abundance. My own students find spool boxes most convenient, and 

 they may generally be obtained at stores for the asking. The substratum must 

 be, of course, taken with the fruiting slime mould, and wherever possible should 

 be cut to fit snugly into some box devoted to its reception. Where this is well 

 done specimens come to the laboratory in all the grace and delicacy of their 

 perfect state. Without such care, satisfactory work can hardly be expected. 

 Of course, where time and circumstances favor, a box of glue may form part of 

 the outfit, and the specimens may be cared for by attaching the blocks on which 

 they rest firmly and permanently to the bottom of the box. But even without 

 glue, the writer has carried delicate material from Oregon to Iowa in perfect 

 safety. 



Once the specimens are in the laboratory, their further investigation presents 

 no special difficulty ; a few suggestions may, however, not be out of place. In 

 the first place, we may proceed to the preparation of our herbarium material. 

 To this end different methods have been employed by different collectors. In 

 the British Museum and in the Schweinitzian Herbarium in Philadelphia, and 

 elsewhere, specimens were cared for by simply placing the material in folded 

 paper packets, which were then mounted on herbarium sheets. It is needless to 

 say that this is not a good method. The material we deal with is generally 

 extremely fragile, and must be absolutely protected. Much of Schweinitz's 

 material has completely disappeared through lack of proper mounting. The 

 most convenient method of dealing with the problem involves the use of small 



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