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Early  Journal  Content  on  JSTOR,  Free  to  Anyone  in  the  World   This  article  is  one  of  nearly  500,000  scholarly  works  digitized  and  made  freely  available  to  everyone  in   the  world  by  JSTOR.     Known  as  the  Early  Journal  Content,  this  set  of  works  include  research  articles,  news,  letters,  and  other   writings  published  in  more  than  200  of  the  oldest  leading  academic  journals.  The  works  date  from  the   mid-­‐seventeenth  to  the  early  twentieth  centuries.      We  encourage  people  to  read  and  share  the  Early  Journal  Content  openly  and  to  tell  others  that  this   resource  exists.    People  may  post  this  content  online  or  redistribute  in  any  way  for  non-­‐commercial   purposes.   Read  more  about  Early  Journal  Content  at  http://about.jstor.org/participate-­‐jstor/individuals/early-­‐ journal-­‐content.                     JSTOR  is  a  digital  library  of  academic  journals,  books,  and  primary  source  objects.  JSTOR  helps  people   discover,  use,  and  build  upon  a  wide  range  of  content  through  a  powerful  research  and  teaching   platform,  and  preserves  this  content  for  future  generations.  JSTOR  is  part  of  ITHAKA,  a  not-­‐for-­‐profit   organization  that  also  includes  Ithaka  S+R  and  Portico.  For  more  information  about  JSTOR,  please   contact  support@jstor.org.   I9IO] CURRENT LITERATURE 39I types of development. In the hemiparasite Melampyrum pretense, GAUTHIER25 found that the seeds germinated without any stimulus from other organisms, and that the seedlings had a short independent existence, during which the roots branched freely. Root hairs developed in abundance, many of them consisting of two or three cells, but before the food stored in the seed became exhausted, the root hairs began to be replaced by haustoria which penetrated the roots of the host. Trees with mycorhiza upon their roots were the hosts, the beech much more frequently than other species. Failure to effect a contact with a suitable host resulted in the early death of the seedlings. . The investigator stated that the seeds, in common with those of Rhinanthus, Euphrasia, and Pedicularis, would not germinate if allowed to become dry. HEINRICHER studied the same species,26 obtaining results essentially similar to the above, but he claims27 that in general the seeds of Rhinanthus, Euphrasia, and Pedicularis are not so sensitive to desiccation, but retain their vitality for several months, although some of them germinate only during the spring. He has studied the group extensively, and in the recent article summarizes the life history of a highly specialized type discussed in a former paper.28 The seeds of Tozzia germinate only with the chemical stimulus afforded by the roots of the host, its cotyledons never appear above the soil, and for two or three years it is a sub- terranean holoparasite. Finally it sends up an aerial shoot which becomes green, flowers, and produces seeds. As the seeds mature the plant dies, each individual flowering once only.-GEo. D. FULLER. Vegetation of the Danish West Indies.-As a result of further study of the halophytic vegetation of the Danish West Indian Islands, BORGESEN2Q has modi- fied somewhat his former classification of the plant societies involved, and now distinguishes a hydrophytic vegetation composed of sea grass and algae, and a halophytic vegetation embracing the muddy soil vegetation, the sand strand vegeta- tion, and the rocky coast vegetation. The muddy soil vegetation is made to include the mangrove, Salicornia, and Conocarpus formations. The author places emphasis upon the influence of exposure and soil consistency as the deciding factors in limiting the mangrove formation, which he defines as a formation of treelike evergreen plants growing on the sheltered shores, partly in shallow salt or 25 GAUTHIER, L., Sur le parasitisme du Melampyrum pralense. Rev. Gun. Bot. 20:67-84. i908. 26 HEINRICHER, E., Die grilnen Halbschmarotzer, V. Melampyrum. Jahrb. Wiss. Bot. 46:273-376. i909. 27 v Germination des graines des plantes parasites. Rev. Gen. Bot. 2 I: 329- 337. I909. 28 , Die grUnen Halbschmarotzer. III. Bartschia und Tozzia. Jahrb. Wiss. Bot. 36:665-752. I90I. 29 BORGESEN, F., Notes on the shore vegetation of the Danish West Indian Islands. Bot. Tidssk. 29:20I-259. pls. ,3-6. i909. 392 BOTANICAL GAZETTE [MAY brackish water, partly on low-lying soil which is rarely, sometimes never, covered by salt or brackish water. While visiting the islands in i906, he noted that the extensive mangrove forest occupying one of the larger lagoons had perished. The explanation seems to be that in i899 the island was ravaged by a serious hurricane, which so violently agitated the sea that large quantities of clay and gravel were washed into the lagoon and deposited as a layer several inches thick. This caused so sudden a change in the soil constitution as to destroy the forest, although there were clear indications that the same formation would eventually reclaim much of the area formerly occupied. The small trees growing in drier situations seem sufficiently distinct from the mangroves to be regarded as a distinct society, which is named the "Conocarpus formation," after the most conspicuous member. This formation is regarded as very nearly the ecological equivalent of the Nipa formation of SCHIMPER in the Indo-Malayan strand flora. The vegetation of the sand strand exposed to the wind includes the well-known Pes-caprae formation, an aggregation of shrubs designated the Tournefortia formation, and the forest Coccoloba-Manchineel formation. The anatomy of several of the strand plants has been investigated, and some further studies made of the more xerophytic vegetation of the rocky coasts.-GEo. D. FULLER. Loess and plant societies.-The intimate relation between physiographic plant ecology and geology receives emphasis in the evidence deduced by SHIMEK30 to prove that the irregular distribution of less deposits has been effected by the character of formerly existing plant societies. Vegetation is known to play an important part in pulverizing the soil, affording anchorage for fine wind-blown particles, and finally in returning its own substance to the soil in a finely subdivided condition. Thus well-drained areas supporting heavy mesophytic vegetation accumulated fine material now appearing as moderate deposits of less of uniform quality. Xerophytic societies of unequal density resulted in inequality and irregularity of the deposits, while hydrophytic areas, as well as those of such eleva- tion or aridity as to be without vegetation, collected no less. The very diverse aspect of the plant societies on the east and west sides of large streams like the Mississippi is found to correspond exactly with the difference in quality and dis- tribution of their less deposits. The interstratification of sand the author believes to have resulted from periods of very scanty vegetation caused by climatic changes. While the thesis is essentially an argument in support of the eolian hypothesis for the formation of less, it has many points of interest for the ecologist; for should further evidence prove the soundness of the author's views, it would afford a useful key to the distribution of plant societies during recent geologic times. The author finds the present edaphic influence of less evident in the vegetation, even 30 SHIM-EK, B., The genesis of less a problem in plant ecology. Proc. Iowa Acad. Sci. I5:57-74. pls. 3-7. 1909.