iSqo.] NEW-YORK MICROSCOPICAL SOCIETY. 



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in the large communities, and the increase in numbers is very 

 rapid. In the seat-rails in the coaches, which were destroyed 

 by Calotermes tnarginipennis Latrie/ie, Mr. Beaumont estimated 

 that nearly one-half of the number of the insects was females. 



The Calotermes are dangerous pests, from their secluded 

 habits. And, with one exception, they scarcely give any indica- 

 tion that they are in wood-work of buildings, coaches or furni- 

 ture. The exception is the presence of little pellets of partially 

 digested wood, about t-V, of an inch long, and yVo of ^" '\x\c\\ in 

 diameter. These are found upon the floor. In eating out the 

 pockets in the wood they are careful to leave a thin partition 

 between adjoining pockets. This is undoubtedly due to the in- 

 stinct of danger from breaking through a surface I have one 

 pocket which probably was one of the first constructed in the 

 wood, and subsequently the wood surrounding it was eaten, 

 leaving it intact, its support being derived from the tube, which 

 was formed by leaving the wood containing the orifice or en- 

 trance to the pocket. No evidence has been found of the Calo- 

 tervies repacking the excavated wood with solid material, making 

 it into nests, as is the case with the Termes. 



Sometimes a pocket will be found partially filled with the 

 loose pellets before mentioned, but the majority are empty. 



Because the Calotermes have no workers, in the sense of the 

 other genera, I do not wish to convey the impression that they 

 are idlers. On the other hand, they are very aggressive and 

 voracious, eating hard, sound woods, which the other genera are 

 not as liable to do. From the fact that the hard, sound wood 

 wears away their mandibles, I am induced to think that natu- 

 rally they live on soft wood or that undergoing decay. 



In a recent communication I partly explained the reason of 

 their ability to eat hard woods, notwithstanding the fact that the 

 wood wears off the cutting portions of their mandibles, /. e., the 

 anterior teeth by which they sever the wood from the block. So 

 far as now observed by Mr. Beaumont, and judging by the spec- 

 imens of insects of the Calotermes sent to me, a large percentage 

 of a community is composed of larvae and nymphae. A nympha 

 will undergo several moultings before reaching the imago state, 

 and at each moult will be provided with a new set of mandi- 

 bles, replacing the older worn ones, and the wood cutting goes 

 on with little interruption. When the mandibles of the imago 



