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J236 BOTANICAL GAZETTE [September 



with the serum of Agaricus. The Tuber extract gave strong precipitation both 



with Tuber serum and with yeast serum, but none with mushroom serum. The 



mushroom extract gave a precipitate only with the serum of the animal treated i 



with mushroom extract- From these experiments the writers infer that the yeast 



is more closely related to the Ascomycetes than it is to the Basidiomycetes. 



While the preciphin method has been used to a certain extent in attempts to show 



relationships among animals, too much stress should not be laid on this single 



experiment with plants. It is possible that albuminous substances from some 



plants may produce preciphins in the blood of animals that will then react with 



many plant albumins, just as it has been found that precipitins in animals will 



affect animals of more and more distant relationship depending on the intensity 



and duration of the treatment of the original animal, — H. Hasselbring. 



Sand keys of Florida.— Millspaugh^^ has published the results of further 

 exploration of the sand keys of Florida. In 1904 O. E. Lansing, Jr. was sent 

 to examine all the islets lying to the westward of Key West, and his collections, 

 notes, and maps form the basis of the present paper. The vegetation of each 

 islet is mapped in a very effective way. The value of the survey is to enable 

 future students to determine what species have come to the different islets since 

 1904 and what have been unable to survive; what species come first to such 

 islets; and how species spread when brought into an untainted environment. 

 In a summary it is shown that such species as are able to avail themselves of bird 

 and water transportation, and can withstand or actually need a saline soil and 

 atmosphere, are the species that lay hold of these islets. Wind transportation 

 appears to play no part whatever in the plant colonization of these minute islets. 



wide study of such areas in the Antillean 



■formed 



of Florida has been as follows, the method of transportation also being indicated: 

 (i) Sesuvium portulacaslrum (water), (2) Cakile jtisiformis (water), (3) Euphor- 

 bia buxifolia (bird), (4) Cenchrus tribidoides and Cyperiis hninneus (bird), (5) 

 Uniola paniculata (water), (6) Andropogon glomeratiis (bird), (7) Suriana ntarit- 

 ima and Tournejorlia gnaphalodes (bird), (8) Borrichia arborescens and Iva 

 imhricata (bird), and (9) Ambrosia hispida (water).— J. M, C. 



Pythium and Chytridiaceae.— Butler has'^ made an extended study of the 

 genus Pythium. The introductory part of his monograph is a somewhat 

 lengthy account of the habits, structure, and biology of the members of the genus. 

 The observations recorded have for the most part been described by earlier stu- 

 dents of the group, and ver}' little that is new is added. An observation relat- 

 ing to the morphology of the sporangia and conidia of the genus is of interest. 



" MiLLSPAUGH, Charles F., Flora of the sand keys of Florida. Field Colum- 

 Kan Mus. Publ. Bot. Ser. 2:191-245. 1907. 



^3 Butler, E. J., An account of the genus Pythium and some Chytridiaceae. 



Mem. Dent. Atrrir. Tnrlia "Rot Q^i-i'i^ t^;- i^t-» ^a^ a/^ ,-^ -. — ^ 



