196 



NATURE 



{July 5, 1877 



regain, actually lived on the plains under the Harz, Dr. 

 Nehring has proved satisfactorily by his own researches. 

 It follows that this country must have formed a steppe 

 during a certain portion of the Diluvial period. 



If the above conclusions are right it follows that in a 

 former epoch those parts of Central Europe which were 

 formerly covered by the sea generally became steppes 

 before coming into their present condition. Perhaps the 

 Magdeburg-Halberstadt steppe extended southwards over 

 Aschersleben and Halle into the valley of the White 

 Elster, for Prof. Liebe has found, near Gera, fossil re- 

 mains of several specimens of the large Jerboa, as also 

 of the Souslik and other animals which have been ob- 

 tained at Westeregeln. Besides, remains of the same 

 animals, as well as those of the Saiga antelope and wild 

 ass, have been found at several other points to the west. 

 It follows, therefore, that the steppe must have extended 

 considerably in that direction. 



The result of these investigations is the more important 

 as manifest traces seem to show that at the Steppe period 

 man had already occupied the plains of middle Europe, 

 and occasionally took up his abode even on the ancient 

 steppe of Westeregeln. 



The cause of the disappearance of the ancient steppes 

 of Central Europe Dr. Nehring supposes to have been 

 the gradual increase of the forests which advanced along 

 with the change of climate. In the Steppe period England 

 and Scandinavia were still joined to the continent of 

 Europe, the North Sea and the East Sea did not exist in 

 their present extent, the Gulf Stream had a more northern 

 direction, and the climate was drier and more severe 

 than it now is. As the climate softened and the forests 

 advanced from the wooded hills, the steppe animals 

 gradually withdrew themselves towards the east, and dis- 

 appeared, leaving only fossil remains to attest their former 

 abundance. 



THE COLORADO BEETLE 



WE have already several times referred to this destruc- 

 tive insect, and now that it has reached Europe 

 we give an illustration of the creature in its various con- 

 ditions, along with some notes which have been forwarded 

 to us by Mr. Andrew Murray. The Board of Trade 

 have reissued the circular, with a coloured illustration, 

 referred to in our article on Our Insect Foes, vol. xv., 

 p. 85. 



The Colorado beetle belongs to that subdivision of 

 vegetable-feeding species known as Phytophaga. It may 

 help the general reader to an appreciation of their place and 

 character if we mention the Turnip flea as a British species 

 of this section, and stiU nearer to it those brilliant green 

 little gems that are to be seen in quantity on the leaves of 

 the white nettle {Laiiiiiim album) in summer, .nnd which 

 in Scotland bear the colloquial name of Virgin Maries, 

 an appellation, however, which is also there sometimes 

 indifferently given to the ladybird. The genus in this 

 great section to which these little insects equally with 

 the Colorado beetle belong is named Chrysomela. It is 

 true that its first describer, Say, named it Dorypliora 

 decciidincata, and that at first that designation acquired 

 such extensive currency that it was all but universally 

 adopted ; and many people from old habit or deference to 

 general usage, even when they know it to be an error, still 

 use it ; but all entomologists know that it is not a Dory- 

 phora, but a portion of the great genus Chrysomela, with- 

 out going into other details. Tne difference between 

 them can be very easily pointed out by one single 

 character. Doryphora is a massive Chrysomela with a 

 strong spike projecting forwards from the middle (the 

 mesosternum) of the under side, while Chrysomela has 

 no such spike. The former is a genus peculiar to the 

 South American region, including Central America, and 

 contains the largest, finest, and most beautiful species of 

 the family. Some of them are somewhat similarly 



marked to the Colorado beetle, which no doubt led to 

 Say mistaking the genus. But although the Colorado 

 species and its allies are clearly enough Chrysomeke, 

 systematists in arranging that genus have broken it up 

 into several !sub-genera or new genera, and the latest 

 authority (Chapuis) has placed them in a genus named 

 Leptinotarsa, but at the same time indicates his opinion 

 that a further subdivision must take place, which will 

 leave the Colorado beetle and its relations in a subgenus by 

 themselves, as was long ago (183 7) proposed by M. Chevro- 

 lat, under the name of Polygramma. For the characters of 

 these subdivisions we refer to M. Chapuis's genera, and 

 for the specific characters of the species falfing under 

 Polygramma to Stahl's diagnosis and Mr. Riley's first 



Larva of Colorado Beetle : natural 

 size.— Note. The double row of 

 black spots along the abdomen is 

 not sufficiently distinct in this cut. 



Missouri Report (1869). These are, first, the true Poly- 

 gramma {Decenilineaia, Say) that has occasioned all this 

 alarm, which is the most northerly species, its native 

 home being the eastern base of the Rocky Mountains and 

 the prairies extending eastward. Next a variety called 

 Multilineata by Walsh and Stahl, but which is not speci- 

 fically distinct. Then a good species, Polygramma 

 juncta, which ranges through the Confederate States of 

 North America, and is easily recognised by two of the 

 dorsal black lines uniting to make one thicker one. 

 Farther to the south, about Vera Cruz and Costa Rica, 

 &c., there is another species very like the Colorado 

 species, called Polygramma undecemlinea/a, Stahl, and 

 which is found in enormous numbers in these parts of 

 Mexico. Lastly Stahl records another, which we have not 

 seen, from Mexico, under the name of novemlincata. 

 All these feed on different plants, although probably 

 plants all belonging to the same order, the Solan aceae. 



NOTES 



The Society of Arts has awarded its Albert Medal " for dis- 

 tinguished merit in promoting Arts, Manufactures, or Commerce, 

 to Jean Bapliste Damas, member of the Institute of France, the 

 distinguished chemist, whose researches have exercised a very 

 material influence on the advancement of the Industrial Arts." 

 The Society's Medals for papers read during the session, have been 

 awarded to Prof. Biarff, M. A., for his paper on " The Treatment 

 of Iron for the Prevention of Corrosion ; " J. Meyerstein, for his 

 paper on " Stenochromy, a Novel Method of Printing in Co- 

 lours;" A. J. Ellis, F. R.S., for his paper on "The Measurement 

 and Settlement of Musical Pitch ; " B. St. John Ackers, for his 

 paper entitled " Deaf not Dumb ;" Commander Cameron, R.N., 



