INSECTS AND SPIDERS 



52^ 



brain, and a windpipe! Their mouth-parts are wholly 

 rudimentary. True spiders have a liver, which no insect 

 with wings is known to have. 



A few years ago, the writer photographed a tarantula 

 one of the giants among spiders that was seven inches 

 across, measured on its ex- 

 tended legs. Relatives of 

 this dangerous fellow in 

 South America and Mex- 

 ico often prey upon hum- 

 ming-birds, which, it is 

 said, they climb trees to 

 capture. 



Others of our spiders 

 weave a beautiful silken 

 sphere about their eggs, 

 carrying it about until the 

 young hatch out ; and the 

 achievements of the trap- 

 door spiders are well 

 known to many. Elegant 

 webs are woven by some 

 species, and many forms 

 are brilliantly colored, be- 

 ing figured and spotted in 

 a way most bizarre. 



We have in the United 

 States a long list of those 

 insects we usually designate 

 as beetles. There are some 

 fifteen thousand different 

 kinds of them, and they 

 range in size all the way 

 from little bits of ones that 

 it almost requires the use 

 of a microscope to see, to 

 such giants as the Spotted 

 Horn Beetle shown in Fig. 

 5 of the accompanying cut. 

 Some of our beetles are 

 of a very plain color often 

 a dead black or lustreless 

 brown, while others reflect 

 all the prismatic colors of 

 the rainbow. During the 

 summer of 1920, the United States National Museum 

 kindly loaned the writer over twenty of the commonest 

 forms of American beetles; a dozen of these he photo- 

 graphed, and a reproduction of this illustrates the present 

 article. All of the beetles thus shown are abundant 

 species in one part of the country or another, and all of 

 them present interesting life histories. Many of the 

 readers of American Fore.stry will recognize some of 

 them on sight ; a few will know all of them, while several 

 of the forms figured in it will be of value to foresters 

 to know, as they have to do with the welfare of, or are 

 more or less injurious to, some of the trees of our forests 

 or to our shade and fruit trees. 



FIG. 4. A CURIOUS SPIDER FROM FLORIDA 



This specimen was captured and presented by Mr. R. H. 

 Young, of Bradentown, Florida, and the reader is invited to 

 note the peculiar hairy tufts between the leg-joints. 



When fully adult, an ordinary beetle may be recog- 

 nized through its having its front or superficial wings 

 hard and stiff, and much thicker than the semi-trans- 

 parent ones they cover. These hardened wings meet 

 down the middle line of the body by contact of their 



inner borders they are 

 called the elytra, and their, 

 line of contact the suture. 

 In a few groups, these 

 elytra do not cover the ab- 

 domen posteriorly ; but this 

 is not the case with any of 

 the beetles here shown. 



Larvae of beetles possess 

 no legs on the abdomen, 

 with the exception of the 

 last joint, where it is not 

 uncommon to find a pair. 

 In the adults, the mouth- 

 parts are constructed for 

 chewing. Running beetles 

 are wingless, as a rule, the 

 exceptions being where 

 these structures are pres- 

 ent but fused together at 

 the suture. 



"Grubs" are the larval 

 forms of beetles. Most, if 

 not all grubs, possess three 

 pairs of jointed legs on the 

 thorax. Among the larvae 

 of the "snout-beetles" we 

 find no jointed legs present 

 whatever, and a study of 

 their structure is a very in- 

 teresting subject, not to 

 say an important one. 

 " With the exception of 

 the Spotted Horn Beetle 

 (No. 5), the writer has col- 

 lected in nature all of the 

 beetles shown in the cut 

 some of them many times, 

 and made notes on the hab- 

 its of each. The only Spot- 

 ted Horn Beetle he observed alive was in New Orleans 

 early in the eighties. It flew into a room of his quarters 

 at Jackson Barracks; and, as it struck the wall and fell 

 to the floor it sounded as though someone had fired a 

 stone at the occupant. As the room was dark the lamp 

 having been extinguished the beetle almost immediately 

 took to flight again, making its escape through the open 

 door. Lutz says of it that "The common name, Unicorn 

 Beetle, is scarcely correct, for the males have three horns 

 on the pronotum, the ones on the sides curved and very 

 short, the median one with yellowish hair beneath notched 

 at the tip, and projecting forward to meet a long, curved 

 horn arising from the head. The females have only a 



