THE PERIODICAL CICADA. 175 



In Louisiana, it appeared in Morehouse, Caddo, Clairborne, Washington, 

 and adjacent parishes, in 1855 and '68. 



It also doubtless occurs in Mississippi and Indian Territory, though I am 

 unable to specify any localities. 



The last simultaneous appearance of these two broods was in 1660, and their 

 appearance the present year will doubtless enable us to perfect our knowledge of 

 the geographical range of either. Already we have received undoubted indica- 

 tions of their early ascension, as the pupge have been reported either near or 

 upon the surface of the ground in several of the localities indicated. 



It will be observed that the thirteen-year brood (xviii), is by far the most 

 extended, and that it occurs very generally throughout the Southern States, both 

 east and west of the Mississippi. We have gathered together since the last ap- 

 pearance of this brood in 1868, various facts which extend its range in Georgia 

 and Tennessee, and whicli show that it also occurs in restricted parts of Indiana. 

 American Naturalist. 



ENGINEERING AND MINING. 



THE TEHUANTEPEC SHIP RAILROAD VS. PANAMA CANAL. 



W. L. SEDDON, TOPOGRAPHICAL ENGINEER, COLUMBIA, MO. 



When inter-oceanic transit was first proposed, science was still in swaddling 

 clothes ; and as to the child many things seem possible, nay, even easy, which 

 to the maturer mind of the man present almost insurmountable obstacles, so in the 

 advance of science the scheme of piercing our rock-ribbed isthmus by a canal has 

 proved a herculean task. But although it be such, in the present development of 

 scientific resource it is folly to say that it is impossible to clear away these bar- 

 riers and let the mighty oceans clasp hands across the breach. We make no 

 such assertion, but we do contend that science in its onward march has done 

 more than simply show the magnitude of the task and furnish means for its ac- 

 comphshment ; that it has brought forward another and better solution of the dif- 

 ficulty, and it is this latter solution, more especially, which we will now briefly 

 consider. 



This proposed plan is not to pierce but to surmount these barriers, to lift the 

 laden ships from the waves by means of our great modern motor, to bear them 

 over these ridges and again consign them to the blue waters on the further side. 

 In short, it is the proposed plan of a Ship Railway. And before we enter upon 

 the discussion of its merits, it is but just to say that were they less apparent, the 



