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pillars will probably have tried " beating," which consists of hold- 

 ing a special apparatus something like an umbrella under a tree,, 

 and then with a stout stick tbresbing the branches above it. On- 

 an examination of tbe contents afterwards, consisting of spiders,, 

 beetles, flies, and grub-looking caterpillars, it will be noticed there 

 are what look like a number of twigs ; presently, to the surprise 

 of the novice, several of these " twigs " will raise themselves up^ 

 and begin to walk off as fast as their legs will carry them. These 

 are the caterpillars of different kinds of geometer moths. It is an 

 extremely numerous family, nearly three hundred species being 

 found in this country ; but, until we beat them from their food 

 plant, they are rarely seen, their great resemblance to their environ- 

 ment helping their concealment. They possess only two pairs of' 

 claspers, while most otber caterpillars have five pairs. Tbese are 

 placed at the posterior part of the body, which is long, thin and 

 round, and stands out like a twig at an acute angle with the stem 

 to which the claspers are tightly fixed. There are often little 

 Lumps on the body which resemble buds or irregularities of the 

 bark. In t)\e day time the caterpillar is quite still, not moving 

 until it needs food, which is generally taken at night. As the 

 maintaining of this position for so considerable a time would 

 cause great tension to the caterpillar, it spins a short thread. 

 of silk, and attaches itself by this to tbe adjacent twig; in other 

 crsis it fixes its If in a fork of the branch, holding by both ends of 

 the body. To complete the resemblance, the head of these cater- 

 pillars is altered from the usual shape into one which suggests the 

 end of a twig " In the caterpillar of the Small Emerald moth 

 [Hcmith a thynnoria) there are two additional humps on the body- 

 ring behind the head, and the latter is bent forwards and inwards, 

 so that the end of the caterpillar is made up of four blunt 

 projections forming perhaps the most suggestive resemblance to 

 the end of a twig." [Colours of Annuals, p. 29). Speaking of these 

 protective resemblances, the late Mr. Jenner Weir says: — " After 

 being thirty years an entomologist, I was deceived myself, and took 

 out my pruning scissors to cut from a plum treo a spur which I 

 thought I had overlooked. This turned out to be the larva of a 

 geometer two inches long. I showed it to veveral members of my 

 family and defined a sp>ice of four inches in which it was to be 

 seen, but none of them could perceive that it was a caterpillar." 

 Last year I was rearing a brood of Acida/m areisata (the riband- 

 wave moth) on knot-grass, and on several successive changes of 

 food I noticed that they were gradually disappearing I then 

 determined to count them, and on the next occasi(i]i I found I was 

 three or four short. I again carefully scanned the rejected fool, 

 but it was not until I passed my fingers down the stems of tite 



