158 Rhodora [September 



The results obtained by the method just described were fully as 

 satisfactory as those secured when a lantern was used as a source of 

 heat, and indeed material could be dried even more rapidly. Under 

 favorable conditions completely dried specimens could be turned out 

 in from three to five hours : specimens in which the natural color was 

 retained far more perfectly than in plants prepared by the ordinary 

 slower methods of drying, and which showed no ill effects from their 

 hot air treatment save a slight smoky smell which soon vanished. 

 Only in exceptional cases was the imprint of the corrugations to be 

 detected in the finished product. Wind and rain were two of the chief 

 enemies with which we had to contend. To avoid the former we 

 always looked for a sheltered pocket among the evergreens where 

 the tripod could be set up. Sometimes we rigged up a make-shift 

 wind-break with a pack-cloth, while in wet wes'.ther a pack-cloth 

 draped tepee-fashion around the top of the tripod served the double 

 end of keeping the press dry and the fire alive. These, however, are 

 two enemies against which on another trip more preparation would 

 be made beforehand. 



As with the lantern method, the d. f. ventilators stood up remark- 

 ably well. They showed some effects of their hard usage, to be sure, 

 and after being in service for a week, with the smoke constantly 

 rising through their pores, they began to smell like a lot of kippered 

 herring, but what real camper would object to that! And notwith- 

 standing that all the ventilators were in practically continuous service 

 for twenty-four days, not one was actually rendered useless. 



In conclusion, a few observations of a general nature regarding 

 the relative merits of the current methods of drying vascular plants 

 for herbarium specimens. The following remarks pertain more 

 especially to field operations, but in large measure they are quite as 

 applicable to herbarium or home practise. In the matter of driers 

 or their " equivalents ", four possibilities are open: driers, s. f. venti- 

 lators, s. f. ventilators plus driers, and d. f. ventilators. Further- 

 more there is the choice between various sources of artificial heat or 

 no artificial heat at all. In deciding upon the relative efficiency of 

 various methods, there are perhaps five principal factors to be taken 

 into account: (1) length of time required to dry specimens and (2) 

 quality of results; and (3) weight, (4) durability, and (5) convenience 

 in handling of the drying equipment. Sufficient objections to driers 

 alone are furnished by the first and third factors; to s. f. ventilators 



