INDUSTRIAL PROGRESS DURING THE YEAR 1871. clxi 



few analogous cases in phaBnogamous plants, that sexual 

 fertilization, however necessary, is not absolutely necessary 

 in every generation of plants. The second article is upon 

 the circulation of sap in trees, by W. S. Clark, President of 

 the Massachusetts Agricultural College, showing the results 

 of numerous and Ions-continued observations made at that 

 institution upon the bleeding of trees, the character of the 

 sap, and the amount of pressure exerted at different heights 

 in the trunk and at different seasons, and also in the roots. 

 Most notable among foreign publications is the French trans- 

 lation, by Van Tieghem, of Sach's great work upon " Vegeta- 

 ble Physiology and Anatomy," made from the third and latest 

 edition, and largely annotated, thus embracing all recent dis- 

 coveries, as well as expressing directly the views of the two 

 highest authorities in this department. Chatin has contrib- 

 uted to the "Annales des Sciences" an important article upon 

 the development of the ovule and seed in several of the 

 monopetalous orders, while the structure of the seeds in the 

 Rafflesiacem and Hydnoracece has been investigated by Count 

 Solms-Laubach (in the "Botanische Zeitung"), confirming 

 the conclusions of Robert Brown respecting the affinities of 

 the first order, but leaving those of the latter still uncertain. 

 The comparative anatomy of the Gnetacece and Coniferoe has 

 been treated by Bertrand in the " Annales," and the struct- 

 ure of the cell-wall in Pinus sylvestris by Dr. Karl Sanio in 

 an extended paper in Pringsheim's " Jahrbiicher," whose con- 

 clusions are criticised and to some extent controverted by 

 Dippel in the " Flora." Fleischer, in the same journal, in a 

 comparison of the embryo of monocotyledonous and of dico- 

 tyledonous plants, shows that the distinct character of the 

 two forms exists from almost the earliest cell-formation. 



The relations and properties of chlorophyl have been the 

 subject of papers by Chautard and Prillieux in " Comptes 

 Rendus," and by Wiesner, Krause, and others. The circula- 

 tion of gases and respiration in plants has been studied witli 

 interesting results by Barthelemy, and by Deherain and Mois- 

 sau, while Haeckel has investigated the phenomena of plant- 

 irritability in certain cases, and by the aid of antesthetics 

 has been enabled to demonstrate in what way motion is 

 produced. 



Collections in the field in our Western Territories have 



