MEANS OF DEFENCE OF INSECTS. 233 



by folding its head under its breast, and turning- up its 

 abdomen over its elytra ; so that the most piercing and 

 discriminating eye would never have discovered it to be 

 an insect. — I have observed that a common beetle (Sil- 

 pha thoracica, L.) when alarmed has recourse to a si- 

 milar manoeuvre. Its orange-coloured thorax, the rest 

 of the body being black, renders it particularly conspi- 

 cuous. To obviate this inconvenience, it turns its head 

 and tail inwards till they are parallel with the trunk and 

 abdomen, and gives its thorax a vertical direction, when 

 it resembles a rough stone. — The species of another 

 genus of beetles (Agatliidium, F.) will also bend both 

 head and thorax under the elytra, and so assume the 

 appearance of shining globular pebbles. 



Related to the defensive attitude of the two last- 

 mentioned insects, and precisely the same with that of 

 the Armadillo {Dasi/pus^ L.) amongst quadrupeds, is 

 that of one of the species of woodlouse {Armadillo vul- 

 garis, Latr.). This insect when alarmed rolls itself up 

 into a little ball. In this attitude its legs and the un- 

 derside of the body, which are soft, are entirely covered 

 and defended by the hard crust that forms the upper 

 surface of the animal. These balls are perfectly sphe- 

 rical, black, and shining, and l)clted with narrow white 

 bands, so as to resemble beautiful beads ; and could 

 they be preserved in this form and strung, w ould make 

 very ornamental necklaces and bracelets. At least so 

 thought Svvammerdam's maid, who, finding a number 

 of these insects thus rolled up in her master's garden, 

 mistaking them for beads, employed herself in stringing 

 them on a thread ; when, to her great surprise, the 

 poor animals beginning to move and struggle for their 



