PROCEEDIXGS OF SOCIETIES. 157
liybrids), of which 2-i have not been figured previously in any icono- graphic work. The pktes are executed by Mr. Tiiornman. Perhaps next to the ' Flora Daiiica ' the most important botanical work produced in Denmark of late is ' L'Amerique Centrale ' of Professor A. S. Oer- sted, the results of journey in Costa llica and Nicaragua in 1846-48. As yet onlv the first part is issued, partly at the expense of the Danish Academy of Sciences. It contains 18 folio pages of letterpress descrip- tive of the physical features of the country, a map, two physiognomical views, and 18 magnificent plates in copper, representing new' species of plants. (Reviewed in .Journ. of Bot. 1865, p. 102.) Oersted has also published an elaborate memoir on the classification of the Oaks, founded on the form of the pistil, venation of leaves, etc., which dif- fers materially from that of De CandoUe and other preceding writers, and is a valuable contribution to the history of the GupuUfercB. To the ' Proceedings of the Academy of Sciences ' the same author has also contributed a paper on the " Silphion " of the ancients, which, from a study of the classical writers, Greek coins, and vases, he con- siders was a species of plant allied to Narthex Asa-fcelida, and which he proposes to call Narthex SUphinm. Professor Oersted's numerous papers on the development of Fungi, his recently published ' Introduc- tion to the Study of Cellular Plants,' bis ' Memoir on the Morphology of the Coniferte,' etc., were also noticed. Of late years Dr. Eugene Warming has visited Brazil, and made collections of plants chiefly in the vicinity of Lagoa Santa. These are now in course of description by himself and other botanists, chiefly Augustus Progel, J. A. Schmidt, Johannes Miiller (Argoviensis), Otto Bockler, C. F. Meissner, A. W. Eiehler, J. G. Baker, Ernst Hanipe, George v. Martens, and Otto Nordstedt. The memoirs of these botanists are published chiefly in the ' Natural History Society's Transactions,' are written in Latin, and contain descriptions and critical and geographical notes of many new or little known species. Warming has published in the same place remarks on the development of heat in PJd- lodendron Lund'd (n. sp.) from Brazil. The development of heat daring the flowering period embraces two calorific undulations. The first day the greatest temperature is towards 6 to half-past 7 o'clock p.m. It then abates and falls to the normal heat during the night. The next day the calorific movement attains its cuhninating-point, 8 to 10 a.m., and ceases towards noon. These observations are made on a plant which flowered from the 16th to 17th of November, 1864. The culminating-points of the ca- lorific iindulation do not coincide with the time when the temperature of the air is at its maximum (viz. 2.30 p.m.). However, there has been observed a certain dependence between them of this kind, that when the temperature of the spadix was more or less high, so also was the temperature of the air. The first period of heat presented the greatest intensity. Not only did the temperature last a ranch longer time, but was more elevated than in the second period. The greatest heat \\hich Dr. Warming has observed, was 39^° C, the temperature of the air being then 23f°, showing a dif- ference of 15f'^. The difterencc in the part occupied by the stamens ivas even higher, viz. 18|^°. The anthers did not open or discharge their pollen until the evening of the second day, after which the caloriflc movement ceased. At the time of the development of heat the inflo- rescence gave forth an aromatic odour, which was much stronger when the temperature was more elevated. The spadix is constantly surrounded
�� �
