SECTION XII. FIELD WORK 

 (MONOCOTYLEDONS) 



A. TRADESCANTIA, TULIP, AND OTHER MONOCOTYLEDONS 



The most common and well-known monocotyledons include 

 the common grasses, sedges, and cereal grains, different mem- 

 bers of the lily family, palms, bananas, and bamboos. The 

 student should consult illustrated manuals and texts in order 

 to form a general idea of the habitat and habit of the mono- 

 cotyledons. Examine also a number of species in the field and 

 in the laboratory, as outlined below, in order to fix the main 

 distinctive characteristics of monocotyledons. Tradescantia and 

 the tulip may be taken as types for special examination. 



1. Habitat. How many of the above-mentioned common 



monocotyledons are widespread or cosmopolitan in 

 habitat ? How many are restricted in habitat ? Are 

 most of these monocotyledons mesophytic, xerophytic, 

 or hydrophytic in habitat and habit ? Can you name 

 common monocotyledons belonging to all three of 

 the above habitats ? Summarize the above facts in 

 your notes. 



2. Habit. Compare monocotyledons with dicotyledons in the 



following particulars of general habit and structure : 

 n. Lc<i/'/'x. 



( I ) Form and venation. What are the distinctive features 

 of the leaves of monocotyledons in these respects ? 

 Note particularly whether monocotyledons have 

 open or closed marginal venation. 



