ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 467 



Pendulation Theory.* — H. Siniroth publishes an account of a theory 

 ~bj which he claims to explain the changes and distribution of living 

 organisms, and to trace back the theory of descent to one uniform 

 cosmic principle. The author supposes that the earth has two fixed 

 poles, between which the north and south axis swings slowly backwards 

 and forwards, and these vibrations indicate the geological periods. The 

 portion of the earth's surface which is most strongly affected by the 

 vibrations lies on a meridian passing through Behring Straits, and is 

 constantly changing its latitude and position towards the sun. The 

 water, under the influence of centrifugal force, acts upon the land, so 

 that dry parts become submerged, and vice versa. The change between 

 land and water gives rise to continued formation of living organisms ; 

 and for this reason the human race and all living things, so far as they 

 can be traced back, arose in the eastern hemisphere, and spread thence 

 in ordered lines over the whole of the earth's surface. The author 

 makes the remarkable claim that all creation, the geological periods, 

 volcanoes, earthquakes, meteorological phenomena, etc., can be explained 

 by his theory. 



CRYPTOGAMS. 



Pteridophyta. 

 (By A. Gepp, M.A. F.L.S.) 



Tropical American Ferns.j— W. R. Maxon publishes the first of a 

 series of studies of tropical American ferns, designed to include notes on 

 some of the earlier species, corrections in nomenclature, revisions of 

 certain genera and smaller groups of species. He first treats of 

 Asplenium salicifolium Linn., and carefully isolates it, showing how it 

 has been misunderstood, and how it has been confused with half a dozen 

 other species. These latter he distinguishes, and adds to them a new 

 species of near affinity. In Holodktyum he describes a new Asplenioid 

 genus founded- on Asplenium Ghieslreghtii Fourn. and A. Finckii Baker. 

 He discusses the identity of A. rhizopliyllum L. ; supplies a new generic 

 name, Pessopteris, to replace Anaxetum Schott ; adds a new species of 

 Adiantopsis to the three already recorded for Cuba ; and describes 

 Ananthacorus, a new genus allied to Vittaria and founded on Pteris 

 angustifolius Sw. He supplies a chapter of miscellaneous notes and 

 corrections of nomenclature ; and concludes with a series of descriptions 

 of twelve new species of various genera. 



Philippine Ferns. — E. B. Copeland % gives a list of new or interest- 

 ing Philippine ferns, among which is a new genus Davallodes, founded 

 on the Leucostegia hirsuta of J. Smith, which was transferred to 

 Mkrolepia by Presl. Copeland adds to it two new species. In other 

 genera he describes four new species and six varieties, and calls attention 



* Die Pendulationstheorie. H. Sirnroth. 



t Contrib. U.S. Nat. Herb., x. (1908) pp. 473-503 (2 pis.). 



J Philippine Journ. Sci., iii. (1908) pp. 31-39 (6 pis.). 



2 I 2 



