PHYSICS AND NATURAL HISTORY OF GENEVA. 105 



expedition of Dr. Hummel in 1S20. Other bones, of the same origin, have 

 been found last spring and still more recently in the same localities. 



BoTAiW. — Memoirs. — Dr. Mnllcr read a memorandum of the monstrosities 

 which he had met with in the flower and fruit of the jatropha pohliana, and 

 deduced therefrom some conclusions on the theory of the anther. He thinks 

 that this i.s formed neither by the combination of two ordinary leaves, nor i)y a 

 leaf whose edges are incurvated towards the median rib so as to form the two 

 chambers of the pollen, lie believes that the anther represents only a simple 

 leaf, and tliat the pollen is developed in the incrassated tissue of the paren- 

 chyma of this leaf. The anthers heretofore recognized are of 1, 2, 4, and 8 

 chambers, and according to the commonly received theory, the existence of 

 trilocular anthers would be an impossibility. Now, in contrrmation of his own 

 theory of the antherian leaf, M. Muller read a note on the existence of trilo- 

 cular anthers in the species pachystema of the family of the euphorbiacse, 

 (Java). The same colleague afterwards presented a notice of two modes of 

 inflection of the stamens in the euphorbiacerc. The only one of these two 

 modes which is noteworthy is that in which the anther is inflected in the bud, 

 its summit below and its base above. This form of inflection is important, 

 inasmuch as it serves to characterize the great tribe of the crotonese. 



Verbal reports. — Professor de Candolle, in his Botanic Geography, has re- 

 marked that the beech and chestnut have not been discovered in Algeria. Now, 

 Professor Martins has recently found chestnut trees in the forest of I'Edding, in 

 the neighborhood of a Roman aqueduct. M. de Candolle conceives that in such 

 a locality the chestnut may well ha\e been introduced by the Romans, and he 

 persists in thinking that the tree in question does not exist in the Atlas. He 

 also noticed a memoir of Dr. Hooker on the arctic flora, a memoir in which that 

 savant seeks to explain why certain regions of the north possess a very rich 

 flora, (Lapland,) while others have an extremel}'' poor one, (Greenland.) M. 

 Hooker thinks that after the glacial epoch the vegetable species, in proportion 

 as the ice withdrew, would ascend into the arctic regions, when those regions 

 were continental, while in the regions which became insular the sea would op- 

 pose the reascension of vegetables. The same naturalist presented the society 

 with grains of the indigenous coffee of Peru ; these grains are more volurainoua 

 than those of the coflVe of Asia, but it is not yet possible to determine their 

 species. He exhibited also the male flower of a begoniacean of Africa, very 

 different from the usual type of its family, for which he had been indebted to 

 the kindness of Dr. Hooker. Lastly, M. Renter presented to the society the 

 leaf, fruit, and part of the flower of the tormclia fragrans, which is the first 

 time that the fruit of this aroid of Mexico has been seen at Geneva. 



Zoology — Mc?noirs. — M. Henri de Saussure read a paper on the incessant 

 dispersion of the hyraeuoptera on the surface of the globe, a dispersion which 

 would have for its apparent consequence a successive modification of individuals, 

 and consequently the development of series of graduated species, marking the 

 stages traversed by the migrations of each type. This hypothesis Avould exr 

 plain the parallel series which may be observed on the same continent or ou 

 difierent continents. Among these successive modifications, one of the most 

 interesting is that which pertains only to one of the two sexes, the feminine. 

 In the genus Elis, for instance, we can distinguish as many as twenty varie-^ 

 ties, spread over all the continents, varieties extremely distinct from one another 

 in regard to the female, but of which the males seem identical or nearly so, 

 which would constitute a series of types successively polygamous. The author 

 concludes by indicating certain species which may have passed from Europe to 

 America, and from America into Africa or Europe. M. Alois Humbert read a 

 memoir, in which he showed, by means of mollusks which he had brought from 

 Ceylon, that in the puknonate ga.stropods there exists no essential difference 

 l)et^,e€B those with an extenial and those with an internal shell, and that it is 



