THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL 



Vol. XIII. 



MAY, 1892. 



No. 5. 



CONTENTS. 



Practical Studies in Biology. — I. 

 The Potato.— OsBORN (Illus- 

 trated) - 105 



Radiolaria : Their Life-History 

 and Their Classification. — 

 Carter - -------m 



How to Collect Desniids.— Hast- 

 ings ---- 1 13 



On Imbedding Animal Tissues 

 in Paraffinefor Sectionizing. — 



OsBORN --------116 



Editorial. — Trip on a Cunard 

 Steamship - - - - - - -iiS 



Microscopical Apparatus . — 

 A Revolving Table - - - 120 



Microscopical Manipulation. 

 Glycerine. Glycerine Jelly. 

 Dead Black. Smith's Method 

 of Drawing 120 



Biological Notes. — Eungus 

 Study. Agassiz. Salmon and 

 Sturgeon in Idaho. CedarTrees 

 and Apple Rust. Arbor Day. 



Diatoms. — To Work the Diato- 

 maceous Earth sent out by this 

 Journal. To Mount Diatoms. 

 Hudson River Fiord - - - 



Bacteriology. — Pas teu r ized 

 Milk. A Bpcterial Disease of 

 the Potato - - - - - 



Recreative Microscopy. — Mi- 

 croscopic Mounts of Minerals 

 in Boxes. Lycopodium - - 



Microscopical Societies. — 

 St. Louis. Washington. Mon- 

 rreal. Omaha. Essex. Iron 

 City. New Jersey. New York. 



New Publications. — Woolman. 



- 124 



125 



126 

 128 



Practical Studies in Biology.— I. The Potato. • 



By H. L. OSBORN, 



HAMLINE, MINN. 



\^Co7iti7me.d from fage <?<?.] 

 WITH FRONTISPIECE. 



We have noticed that the potato is really a plant-stem, with 

 pith and bark and buds, both lateral buds placed in a definite lo- 

 cation in obedience to a fixed law of plant growth and a terminal 

 bud. We are justified therefore, in spite of its unusual situation 

 below ground where we commonly look to find roots, not stems, 

 in comparing the tuber with other stems. Other examples of 

 stems growing below the ground are not wanting ; thus the pea- 

 nut is a ripened fruit-pod which matures in the ground, and is 

 demonstrable to be an underground stem ; the onion is also a very 

 short stem ; when it is planted in the ground its terminal bud 



