clx GENERAL SUMMARY OF SCIENTIFIC AND 



physiological groups, which he supposes to have been de- 

 termined by secular changes of temperature in the earth's 

 climate. 



A Flora of Norway has appeared from the hands of Axel 

 Blytt, of Stockholm ; and that of Spain, commenced some 

 years ago, has been continued by Willkom and Lange. In 

 Germany, the few systematic botanists have shown their 

 usual diligence. The elaboration of the Eapliorbiacem of 

 Brazil has been completed for Martius's "Flora" by J. Miil- 

 ler, to which also the Polygalacece have been contributed by 

 A. AY. Bennett. The Pomarece have been revised by Dr. 

 Wenzig in the "Linnsea," and the Gyperacem of the Berlin 

 Herbarium by BOckeler; while in the "Flora" Wawra has 

 continued his Flora of the Hawaiian Islands. Of the Russian 

 botanists, Maximowicz has published additional contributions 

 to the flora of Japan and Eastern Asia, making frequent ref- 

 erence to the allied American species ; the Oriental Labiatm 

 have been worked up by Bunge ; and the genus Vitis has 

 been again the subject of a monograph by Dr. Regel. 



Much attention has been given during the year to the in- 

 vestigation of those plants which are known as insectivorous, 

 and much light has been thrown upon the whole subject. 

 Mr. Darwin and Dr. Hooker, in England, have paid especial 

 attention to the sundews and Asiatic pitcher-plants (species 

 of Drosera and Nepenthes) ; and in this country the Sarra- 

 cenias have been studied by Dr. Mellichamp, the Diona3a by 

 Mrs. Mary Treat, and the Darlingtonia and Droseras by Mr. 

 TV. M. Canby. It seems clearly established that these va- 

 rious plants are in their different ways constructed expressly 

 for the entrapping of insects, and that the prey passes through 

 a process of digestion and absorption, apparently for the sole 

 purpose of the nourishment of the plant. 



Work in anatomical and physiological botany has been 

 confined chiefly to the botanists of Germany and France, 

 though two important papers have been published in Amer- 

 ica. One of these is by Dr. W. G.Farlow upon the occurrence 

 in some ferns of an asexual growth from the prothallus, the 

 plant being reproduced from the spore without the forma- 

 tion of the ordinary sexual organs. Dr. Gray notes that this 

 should probably be considered a case of parthenogenesis, 

 going to prove, if the facts hold good, in connection with a 



