MODERN SCIENTIFIC GEOGRAPHY. 713 



in these animals. It is often connected anteriorly with a median 

 frontal ganglion (Fig. 7, E), lying anterior to and below the brain, 

 which supplies branches to the mouth and adjacent parts. This oral 

 or frontal ganglion, besides being connected with the brain, also gives 

 origin to a median recurrent nerve (e). This nerve is connected with 

 other branches, proceeding from one or two pairs of lateral ganglia (c), 

 near to, and taking origin from, the oesophageal cords. The system 

 of nerves thus derived furnishes branches to the stomach, the intes- 

 tines, and other viscera. In addition, we meet in insects with another 

 well-developed set of visceral nerves, taking origin from a chain of 

 minute ganglia, which lie upon and are connected with the large 

 ventral ganglionated cord. These nerves are distributed to the ex- 

 tensive and greatly multiplied air-tubes, or respiratory organs. They 

 are known to anatomists as"uervi transversi," and are much more 

 developed in insects than are its representatives among any other 

 class of arthropods. 



-- 



MODEEN SCIENTIFIC GEOGEAPHY. 1 



By Dr. HEEMANN J. KLEIN. 



AMONG the various branches of natural science which have in re- 

 cent times attained a high development, geography holds a prom- 

 inent rank. By this, however, we must understand, not so much that 

 vast regions of previously unexplored country have been made known 

 to the educated world ; that rivers, seas, and mountains, have been dis- 

 covered, and the courses of known streams more accurately defined in 

 maps ; but rather that geotectonic 2 data, of which a rich store has been 

 collected, have been studied from broad and general points of view, 

 and the individual phenomena ranged in the order of cause and effect. 

 In earlier times geography was simply a catalogue of facts, and the 

 earth's surface an ultimate datum ; but nowadays we are beginning 

 to regard the superficies of our planet as a result, to investigate the 

 relations between its separate parts, and to note the changes which 

 occur in it. In the words of Karl Patter : " Scientific geography by 

 no means regards our planet as a lifeless, dead aggregate of an unor- 

 ganized nature, or, as Herodotus expresses it, a disk turned on a lathe ; 

 but as a truly and specially organized body in steady process of 

 development, bearing within itself the life-germs of further evolution. 

 Herein consists its unity ; and it is in virtue of this, its living princi- 

 ple, that it is a whole, lending itself to an orderly presentation and 

 development of its great system. Furthermore, it is this which 

 makes of it a science instructive to the human mind an indispensa- 



1 Translated from the German by J. Fitzgerald, A. M. 



2 Relating to the earth's structure. 



