122 BULLETIN 67, UNITED STATES NATIONAL MUSEUM. 



help to keep out insect enemies; if for a long sea journey, a little 

 carbolic acid poured on the outside of the box will prevent mold. 

 It should be remembered that insects imported from abroad are 

 subject to customs duty of 10 per cent on unmounted and 20 per 

 cent on mounted specimens. 



Many of the leading entomologists in the United States are willing 

 to name specimens sent to them for that purpose, provided, of course, 

 they are permitted to keep any specimens that are new to their 

 collection. Most of these specialists do this work in their leisure 

 moments, and the sender should, therefore, do all he can to lighten 

 the labor of identification. The specimens should be sorted in groups 

 in the boxes as far as possible, and each specimen or each species 

 should have a number. In sending Lepidoptera or other insects with 

 large spread of wings they may be "shingled," that is, the specimens 

 may be pinned obliquely backward, so that the wings overlap the 

 specimens in front and to the side. This saves much space. Many 

 collectors put a thin layer of cotton over the cork of a shipping box; 

 this sometimes saves legs and abdomens. 



COLLECTING ARACHNIDA AND MYRIOPODA. 



Spiders (fig. 1 78) , mites, thousand-legs, etc. , are not insects, but belong 

 to several related groups. The spiders and mites are Arachnida, dis- 

 tinguished by having eight 

 legs and only two parts to 

 the body — the front part, 

 known as the cephalothorax 

 and bearing the legs, and the 

 hind part, called the abdo- 

 men. The true spiders, or 

 Araneida, have no segmen- 

 tation to the abdomen, which 

 is attached to the cephalo- 

 pig. i7s.— a spider, peucetia viridans. (After c<>M- thorax by a slender pedicel. 

 ST0CK) This cephalothorax in front 



has eight simple eyes, and below in front is a pair of stout jaws, man- 

 dibles or chelicerse. The palpi are short, leglike appendages near the 

 mandibles. At the tip of the abdomen are four or six little proc- 

 esses, close together, the spinnerets. From these spinnerets issues 

 the silken thread that spiders use to make their webs, cocoons, etc. 

 The majority of spiders do not make a web, and live by hunting for 

 their prey. The orb-weaving spiders (Epeirida?) (fig. 179) make a geo- 

 metrical or orb web, like spokes of a wheel, with cross threads; and 

 there wait, head down, on the center of this web until some insect 

 falls into it. The tarantulas (Theraphosidse) are the largest spiders 

 and have very hairy bodies and legs. Many of them live in holes, 



