84 



THE AMERICAN ENTOMOLOGIST. 



Joseph June 17, did not come from (lie nioun- 

 liiins or even from Colorado. The varioiis states 

 of advanccmet in j,nowth at diirereiit points 

 without rc<?aid lo latitude, elevation, or climate, 

 show that the broods are local, or were local 

 the present year. Their invasions of the coun- 

 try east of the Rocky Mountains, as ^iven in 

 (he December (1868) number of the Am. En- 

 tomologist, 1H20, 185(5, l«o7, l.H(U, IHGC, 1867, 

 and 18(58 (Taylor, Smithsn. Uep. 18.-)8 adds 

 18.")5), show that (hey are not governed by any 

 regular periodic habit or influence. Observa- 

 tion shows that ordinarily their habits on the 

 plains are very similar to those of the Ked- 

 loggcd Grasshoiiper (C. femur-ruhntm, De 

 Ge(M-). I am inclined to the opinion (hat damp 

 seasons arc unfavorable to their development 

 (but I will not take (ime at present (o give my 

 reasons for (his opinion). 



Do they cross the plains from the mountains 

 in one season ? Or, does the same swarm travel 

 this distance? I cannot answer positively. No; 

 yet I am of the opinion that they do not. But it 

 may be asked, " Upon what do you base this 

 opinion ?"' 1 . The opinion of those in Colorado 

 with whom I conversed on the subject (yet it is 

 but an opinion) is that no one brood travels 

 more than thirty to fifty miles. 2. The distance 

 is so great that it raises the presumption (hey 

 do no(, which must be rebutted by some proof, 

 which, so far as I am aware has not been fur- 

 nished—unless their appearance in Kansas from 

 the west be taken as such proof. 3. As they 

 depend upon the wind— near (he mountains— 

 to carry them, it is very likely they depend upon 

 it on the plains. And as they are really battling 

 against the wind during the flight, their progres's 

 is somewhat slow. Hence it would require a 

 long-continued series of favorable winds (o 

 bear them so great a distance. (Be it remem- 

 bered I have seen them flying only in (lie moun- 

 tains, and on the plains near the base of the 

 mountains), t. If they alight on (he plains, as 

 they often do in the mouiKains when (he wind 

 suddenly ceases blowing, coming down like a 

 pebble, their wings would be worn out by the 

 cacli and rough plants, long ere (hey had 

 traveled five hundred miles. ,">. The swarms 

 which come from the inounlains (o the plains 

 near the ba^ e certainly do not proceed lar east- 

 ward. What reason then have we for believ- 

 ing the next brood arising from (heir eggs will 

 enter upon so long a journey? 



But this matter cannot bescilled uiiiil more 

 facts have been' obtained. 



There appear to be several varieties, varying 

 from a straw-color to a dark brassy or greeiii.«ih- I 



brown, the head and sides of the thorax often 

 almost black, yet retaining all the other mark- 

 ings. Age appears (o deepen (he color. 



Yours, etc., trulv, C. Thomas. 



I)K Soto, Ills 



AN K\T(l.M0LO!JIST C.A["OHT NAPi'lXli. 



Amcrican-i. most of them having been raise 

 in a timbered country, naturally consider (ha( 

 he normal condKion of the earth is to be cov 

 ered by forcvts of trees. Hence we can scarcely 

 take up a scienlinc journal, without finding 

 some ingenious new theory to account for the 

 e.Kistence of our western prairies. Tlitjse phi- 

 losophers forget that, in the interior of Austra- 

 lia, on the Pampas of South America, and in (he 

 great African Sahara, you may (ravel for thou- 

 sands of miles without seeing a single tree: and 

 that it is no more the normal condilion of (he 

 earth to be covered by a dense growdi o( woody 

 plants, (ban it is to be covered by a dense growth 

 of herbaceous phenogamous plants, or a (hick 

 carpet of lichens and mosses. To every soil and 

 climate a peculiar vegetjition is api)ropria(ed; 

 and it is as ridiculous to say (hat (rees arc the 

 natural and nornnil growth of (he whole surface 

 of the earlh. as it is to maintain (hat twelve is 

 (he normal and natural number of a jury. 



It is amusing to see how men who live in a 

 grass country hold precisely (he contrary 

 doctrine (o (hat held by those who have 

 been reared in a timber country. "(Jrass 

 especially," says the English entomologist, 

 John Curtis, "is the xatural coveuing ok 

 THE son,, which has been increasing in depth 

 and bulk from the creation." {Farm Insects, 

 p. 498). If Curtis had not been better in- 

 formed in entomology than he seems to be in 

 botany, his works would not find so many read- 

 ers as they do. Entomologists and odier special- 

 ists will generally find i( (he safest course not to 

 meddle with subjects that they do not under- 

 stand. "Let no( (he cobbler go beyond his last." 



THE PKtHfUESS OP THE POTATO lil tJ. 



An interesting account of the Colorado Po(a(o 

 Bug (Dori/jiliofa lO-lineata, Say), is given in 

 some of (he former numbers of the Amekican 

 EsTOMoi.ocjST. It states that, stardng eas(- 

 ward from the Rocky Mountains in 185tl, (his 

 insect had already in 18(>8 reached (he soudi- 

 west corner of Michigan, and Danville in Indi- 

 ana, about (he centre of that State; making its 

 average annual progress about sixty-two miles. 

 Another writer says that " the southern columns 

 of the giaml army lagged far behind the north- 



