208 L. R. CLEVELAND. 



tained is not given, and for this reason we have no way of judging 

 their accuracy. Regarding this experiment Oshima remarks: 

 "It is quite obvious that the amount of cellulose is the main 

 difference between the constituents of camphor wood and those 

 of the nest. As there occurs no decrease of noncellulose, it is 

 clear that cellulose has been taken as the food when camphor 

 wood passes through the alimentary canal; and noncellulose, that 

 is lignin, which is produced as a decomposed material of ligno- 

 cellulose by special function of the alimentary canal, is discharged 

 as the building material of the nest." 



Obviously, Oshima's data do not warrant the conclusions which 

 he draws from them, for it is impossible, without doing a quanti- 

 tative experiment, to establish the fact that lignin is not used as 

 food and that cellulose is, since both substances appear in the 

 wood and in the nest. Oshima completely disregards purposely 

 or ignorantly it is impossible to say all substances which are 

 present in the wood except cellulose and lignin. The fact that 

 lignin is present in the feces (and the test used is not a test for 

 lignin at all) does not prove that it is not used by the termite as 

 food, for cellulose is also present in the fecal material and has to 

 pass through the alimentary canal many times before it is used 

 up. Perhaps it is all never converted into cellobiose and glucose. 

 Then, it has not been shown that termites do not use lignin as 

 food; nor has it been shown that they do. 



Oshima (1919) fed cotton wool to Coptotermes formosanus and 

 claimed that these termites lived more actively on this substance 

 than when fed softwoods, the reason being, so he thought, that 

 the softwoods have a lower percentage of cellulose. But the 

 softwoods do not have a lower percentage of cellulose at least 

 those that have been anlayzed do not have. However, hard- 

 woods average about 100 per cent, higher in pentosan content 

 than softwoods. But Oshima's experiment has no value what- 

 ever, since the number of termites used and the length of life, 

 when given a cellulose diet (Oshima's diet of cotton 1 ), is not 



1 Purified cotton yields an ash ranging from o.io to 0.50 per cent., while raw 

 cotton contains about i per cent, of mineral matter. Ra\v cotton contains about 

 90 per cent, cellulose and absorbent cotton 99 per cent. There is about i per cent . 

 of pentosan in purified cotton. Most any filter paper, then, is a better rrllulu-'' 

 diet than cotton in any form. Some filters contain an extremely small pen vnui.m- 

 of ash. Of course it .cannot be said that the cellulose of filter paper is "normal" 



