1 882.] Botany. 43 



The Asfaragus Stem for Laboratory Study. — This plant 

 affords as interesting and instructive an example of the stem of 

 Monocotyledons as the now generally used pumpkin stem does 

 of the Dicotyledons. It is so common that every botanical labora- 

 tory can be supplied with it, and its early appearance, and long- 

 continued growth make it possible to secure fresh specimens 

 during many months of the year. The new shoots, such as are 

 sold in the markets, if placed in alcohol afford good material for 

 study, although we have found it a better plan to make all the 

 sections we wanted of fresh stems and then to preserve these sec- 

 tions in alcohol. Thus some cross and longitudinal sections of 

 the very young stems we made early last year are still in most 

 excellent condition for study. Not the least interesting feature of 

 the asparagus stem is its provision for increasing its diameter by 

 the subsequent formation of fibro-vascular bundles in a sub-corti- 

 cal meristem zone. This will afford material for much careful 

 study on the part of students in the laboratory. 



The Abundance of Fresh-water Alg/e.— The excessively 

 wet autumn in Central Iowa caused an unusual growth of fresh- 

 water Algae. Every pond and ditch was filled with Spirogyra, 

 Zygnema, Vaucheria, etc., until the first of November. Usually 

 our waters are nearly barren of these growths so late in the 

 season, but this year the continued wet weather, instead of the 

 usual drouth, favored their development. The same causes doubt- 

 less produced the unusually large amount of autumn blooming of 

 our spring flowers which was noticeable at the same time. 



The Systematic Arrangement of the Thallophytes. — If we 

 except England and America, where a morbid conservatism 

 seems to prevail, there has been a great deal of activity recently 

 among botanists with reference to a better arrangement of the 

 plants lying in the great region below the mosses, and to which 

 Endlicher gave the name of the Thallophyta. Thus Cohn, in 

 1872, published in Hedvrigia,*^ outline of a classification, in 

 which the old groups Algae, Fungi and Lichenes were no longer 

 maintained in their integrity. Shortly afterwards (in 1873) 

 Fischer proposed an arrangement which bears a striking similar- 

 ity to Sachs'. These two are briefly given in our " Botany for 

 High Schools and Colleges," and need not be repeated here. 

 Sachs' now famous arrangement was published in the fourth edi- 

 tion of his Lehrbuch, which appeared in 1874. This has been 

 somewhat modified by various authors, notably by Professor A. 

 W. Bennett, who, in 1880, proposed to restore the groups (classes) 

 Algae and Fungi, subdividing them, however, into sub-classes by 

 making use of Sachs' structural characters. This was republished 

 in the Naturalist for January, 1881. 



De Bary, in January of the present year, published in the 

 Botanische Zeitung a scheme of a systematic arrangement of the 



