TUF STKM 51 



Draw enough of the stem or steius to show the points discovered 

 (x:3). 



Crocus. — Remove the scales. AVhat is the morphology of the 

 denuded bulb? 



Draw the stem, showing iiodet!, inlernoiles, huils, sloUms (under- 

 ground, propagative branches), if present. 



Cut a cross section. Is the plant monocotyledonous or dicoty- 

 ledonous? Test for starch. What is the life history of this pLant? 



Flowering Quince (^Ci/doiiia Japonica). 



Draw a tlioni, bearing a lateral bud, with accessory buds at the 

 base, and the subtending leaf scar ( x 3). 



Boston Ivy (^Ampelopsis Veltchii}. — Are the tendrils associated in 

 any way with leaves or leaf scars? Answer in drawing (x3). Ex- 

 amine the tendril itself with the lens. Are there any indications of 

 leaf formations at the bases of the bravjches? Answer in drawing 

 (xo). What is the use of the flattened ends of the branches? In- 

 clude these disks in one of the drawings. 



VIII. THE STEM 



69. The stem is the axis of the plant and the stock from 

 wliicli spring all the other organs. Side steins, or 

 branches, spring from just above the axils of the leaves. 

 Leaves are present on tlie stern of every flowering plant at 

 some stage of its existence, tliough they may often be 

 reduced to the merest rudiments. This is the case with 

 stems that run along beneath the surface of the soil, where 

 leaves would be of no use. But the tendency to produce 

 leaves never quite disappears, and on underground stems 

 manifests itself in scales and prominences at more or less 

 uniform distances ; the joints or nodes thus made, serving 

 to distinguish such stems from roots, which they otherwise 

 closely imitate. 



70. The stem of an annual herbaceous plant is composed 

 largely of living tissue, and is commonly seen to be green, 

 pulpy, more or less translucent, and full of sap. A few 

 strands of woody fiber run through it ; but the genei'ul 

 mass is succulent, and abounds in living substance. As 

 age and height and the weight of foliage and fruit in- 

 crease, woody strengthening tissue may be largely devel- 



