MOUNTING INSECTS. 



or of some good elastic glue, on the tip of a triangle and 

 touch it to the underside of the thorax. Some difficulty 

 will be experienced in keeping the insect straight on the 

 point, especially if the adhesive be too thin. The triangles 

 for ants should be fairly broad at the "point," and the 

 front end of the abdomen as well as the thorax should be 

 supported. 



The method just mentioned is almost universally used 

 for small beetles. Small flies and the like are frequently 

 mounted on "minuten nadeln." These are short, very 

 delicate, headless pins. Bits of pith, cork, or firm blotting 

 paper (used edgewise), serve to connect nadel and a 

 regular pin. The nadel may be stuck through the insect 

 and then into the support. A somewhat better plan is to 

 arrange a number in advance by sticking the nadel through 

 the support from below, leaving the point stick up; then 

 mounting can be rapidly done by piercing the insects 

 from below. It is well, in this case, to stop before the 

 point comes entirely through the back as then no pin 

 shows and furthermore the characters on the back are not 

 marred. "Minuten nadeln" have the advantage over 

 glue on triangles that the glue does not always hold. On 

 the other hand, they cannot be used with many hard- 

 shelled beetles. Elbow pins are sometimes used but are, 

 as a rule, not very satisfactory. All mounts mentioned in 

 this paragraph are usually put on the left side of the pin. 



The height of the insects on the pin is important for the 

 final appearance of the collection. A strip of cardboard 

 whose width is % to V 3 the length of the pin makes a 

 convenient gauge. With one edge held at the head of the 

 pin push the insect up until it touches the other edge. 

 Or a block of wood containing a hole whose depth is % 

 to T / 3 the length of the pin may be used. Devices for 

 regulating the height by sticking the point of the pin into 

 a gauge are not satisfactory because of the varying thick- 

 ness of the specimens. 



Mounting insects in balsam on glass slides will probably 

 not be taken up by the general collector unless he be al- 

 ready accustomed to making balsam mounts. It is, 

 however, the only satisfactory method of getting extremely 

 small forms ready for study. 



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