240 Rhodora [OCTOBER 
saprophytes seem especially attractive to insects. The Leguminosae 
and herbaceous Liliaceae also form vulnerable spots in an herbarium. 
In such groups as the Coniferae and Typhaceae, the staminate 
inflorescence is the chief point of attack. 
The “herbarium beetle ” is capable of eating almost any part of 
the plant, and includes lignešcent stems and sometimes glue or even 
portions of the herbarium sheet in its diet. The book-louse, on the 
other hand, being especially attracted by pasty or saccharine sub- 
stances, confines its injuries to delicate parts of the flower, chiefly 
the petals, anthers, and nectaries.' 
Besides the insects mentioned, there are others peculiar to certain 
groups of plants, such as the gentians, irises, Peltandra, etc. These 
creatures, deposited as eggs in the base of the flower during the life 
of the plant, are apt to cause considerable annoyance by their ravages 
during and shortly after the drying of the specimen. The expedient 
of a short bath in steam or boiling water is only partially successful, 
since it usually results in a discolored or otherwise damaged speci- 
men, How best to combat these most insidious insect enemies is a 
problem, to which it is hoped some amateur with leisure for experi- 
mentation and a taste for the refinements of herbarium technique 
may turn his attention. Probably the simplest way to avoid the diffi- 
culty in the case of the particular plants is to prepare specimens in 
some quantity and discard those injured while drying. 
The burning of sulphur, practiced at some herbaria, to destroy 
insects, has never been tried at the Gray Herbarium, as it is difficult 
to feel quite satisfied that the methods ordinarily employed can be 
applied on a large scale without a slight fire danger. Furthermore, 
sulphurous acid exercises a strong bleaching action, and would be 
likely to affect the ink of the labels, even if not the plants themselves. 
While the results of the experiments at the Gray Herbarium force 
us somewhat reluctantly to the belief that carbon bisulphide fumiga- 
tion is the most efficient means of preventing insect depredations 
in herbaria of large size, I would not be taken as discouraging those 
who are employing corrosive sublimate. Several amateur botanists, 
with excellently appointed herbaria, ranging from ten to fifty thousand 
sheets, have told me that they have found the corrosive sublimate bath 
l The carpet beetle (Anthrenus varius) and its larvae are occasionally found 
among herbarium sheets, but it has not been possible to ascertain whether it does 
any damage to the plants. 
