[67] COLLECTING AND PRESERVING INSECTS RILEY. 



and specimens of the Aphides, representing all the forms present, should 

 be mounted on slides for microscopic examination. The fixed forms 

 of Coccids, comprising the majority of the species, require no special 

 treatment, and the leaves, twigs, or bark on which they occur may be 

 pinned at once and placed in the collection. The free forms are treated 

 as in the case of plant-lice. 



ENTOMOTAXY. 



Under this term may be considered the preparation of insects for the 

 cabinet. 



CARE OF PINNED AND MOUNTED SPECIMENS. 



Insect Pins. In mounting insects for the cabinet, expressly made 

 entomological pins should be used. These come from three different 

 sources: Klager pins, made by Hermann Klager, Berlin, Germany; 

 Karlsbad pins, made by one or several firms in Karlsbad, Bohemia, 

 Austria; and Vienna pins, made by Miller, Vienna, Austria.* These 

 three kinds of pins have each their own slight advantages and dis- 

 advantages, so that it is difficult to say which is the best. All have the 

 disadvantage that the pinned specimens are liable to be ruined by 

 verdigris, and to obviate this japanned ( u biack") insect pins are made 

 by Klager and Miller. These black pins are, however, much softer 

 than the "white" pins, and therefore more difficult to handle, A pin of 

 35 millimeters in length will be found most convenient for pinning all 

 insects excepting the larger Lepidoptera and other heavy-bodied insects, 

 for which a longer pin may advantageously be used. According to the 

 different degrees of fineness, the pins are numbered from. No. 00 (the 

 finest in the trade) to No. 7 or 8, but the numbers used by the different 

 manufacturers do not correspond with each other. In experience, pins 

 of Nos. 1, 2, 3, and 4 (Klager numbers) are more often needed than the 

 others. The long pins of the finer numbers (Nos. and 00) are difficult 

 to handle in the collection and, for this reason, not to be recommended. 



For many small insects, especially Microlepidoptera and Microdiptera, 

 which must be pinned, even the finest ordinary insect-pins are too large, 

 and two special makes of pins are in use for this purpose. The " elbow 

 pin" (formerly made and sold by Dr. Knenow, of Konigsberg, Prussia, 

 Germany) consists of a piece of fine silver wire, pointed at one end, 

 and with a coil loop at the other end, into which a longer pin (No. 3 or 

 No. 4) is thrust. This pin is illustrated in Fig. 94. Still more sat- 

 isfactory are the "Mmutien-Nadeln" (pins for minute insects) manufac- 

 tured by Mr. Miller, of Vienna, Austria, and which consist of a straight 

 piece (aoout 14 mm . long) of extremely fine steel wire which is pointed at 



* In North America, Kliiger pins and Karlsbad pins can be obtained through Mr. 

 John Ackhurst, 78 Ashland Place, Brooklyn, N. Y., and possibly also through Messrs. 

 Blake <fc Co., 55 North Seventh street, Philadelphia, Pa. The Vienna pins and the 

 Minutien-Nadeln have to be ordered direct through the manufacturer, Mr. Miller. 



