Branch-cutting Beetles ^). 



It is rather curious that thc story wliich Mr. Ober was told in thc Carrib- 

 bees (Nature, vol. xxii. p. 216) should be generally believed in Southern Brazil 

 also, viz., that a large beetle "seizes a small branch of a tree between its enor- 

 mously long nippers, and buzzes round and round the branch tili this is cut of." 

 Only in the Antilles this cutting of branches is attributed to a huge Lamellicorn, 

 the Dynastes lierciiles, and in Santa Catharina to a large Longicorn, the Macro- 

 dontia cet'vicomis. 



Everybody here will teil you this story, but nobody, as far as I know, has 

 ever seen the beetle at work. Branches are often cut off by some animal. On 

 a camphor-tree in my garden six branches, from 9.5 to 13.5 centim. in circum- 

 ference, have been cut off; and on a Pithecolobium for some time almost every 

 morning a fresh branch had fallen down, some being' even much thicker than 

 those of the camphor-tree. The cutting is always in a plane perpendicular to 

 the axis of the branch, as it would be were it made by a rotating beetle ; but in 

 this case an annular incision of equal depth all round the branch would be pro- 

 duced, and this I have never seen. On the contrary, the incision, which, causes 

 the branch to break off, consists of two parts, occupying the lower and the upper 

 face of the branch, meeting on one or on either side of it, and being separated 

 by a wedge-shaped interval, which is broken by the weight of the branch, and 

 is narrower or broader according to its toughness. 



Once — many years ago — I came to the Pithecolobimn tree early in the 

 morning, when a branch was just falling down, and with it came down the ani- 

 mal by which it had been amputated. It was a Longicorn beetle, the well-named 

 Oncideres aniptitator , Fabr. I have since seen specimens of some other species 

 of the same genus, which had been caught by others in the act of cutting bran- 

 ches. It is almost unnecessary to add that they do so by gnawing, and not by 

 whirling round the branches. 



Blumenau, Santa Catharina, Brazil, 13. August 1880. 



i) Nature 1880. Vol. 22. p. 533. 



