388 VARIOUS PLANT GROUPS 



The grain-like fruit of tyjiical grasses resembles an achene 

 in being the product of a t^imple pistil with one ovule and in 

 being dry and indehiscent. It differs mainly in having the 

 seed-coat adherent to the pericarp. A fruit of this kind is 

 distinguished as a caryopsis^ 



As shown in Fig. 9 the embryo is placed at one side of 

 the all)umen. On the side toward the seed-food is a some- 

 what shield-shaped organ, termed the scutelhmi,^ through 

 which the germ absor])s its nutriment when sprouting. Mor- 

 phologically the scutellum is regarded by most botanists as 

 the cotyledon of the embryo, enlarged and otherwise modified 

 for its peculiar function. Unlike the embryo of dicotyledon- 

 ous plants, the emliryo of a grass, as of all the sub-class of 

 seed-plants now to be studied, has but one cotyledon and is 

 hence described as monocotyledonous.^ 



Grasses may be easily recognized as mostly herbs ivith 

 hollow, cylindrical stems; parallel-veined, two-ranked sheathing 

 leaves; flowers enclosed by glumaceous bracts; and fruit a cary op- 

 sis. 



144. The grass order (Graminales or Glumiflorae) com- 

 prises grass-like plants ivith glumaceous bracts, a one-celled 

 superior ovary, and a solitary ovule. 



The formula of Graminales is given on pages 422, 423. 



145. The palm family (Palmaceae). Examples: coconut 

 (Figs. 34-36, pages 46, 47), date (Figs. 108, 109, pages 100, 

 101), sago palms (Figs. 116 I-III, pages 109, 110), rat- 

 tans (Figs. 223 I, II, pages 237, 238), and vegetable ivory 

 (Figs. 266 I, II, pages 275, 276). 



The formulas of Phoenix, Cocos, Calamus, Metroxylon, Phj'^tele- 

 phas, and Palmaceae on pages 422, 423. 



Although in our examples the leaves are all pinnate and 

 compound, many m^embers of the family have simple palmate 

 leaves, as for instance those from which the familiar palm- 

 leaf fans are made. 



' Car"y-op'sis < Gr. karyon, nut; opsis, resemblance. Its mor- 

 phology is indicated in a formula b.y [CE/ < GIN. 

 2 Scu-tel'lum < L. a little shield. 

 " Mo"no-cot"y-led'on-ous < Gr. monos, one. 



