9 
pair of pistillate spikelets. The name ‘‘fruit case’’ was 
apparently first used by Mangelsdorf and Reeves (19389) 
to designate a structure protecting the caryopsis in the 
Maydeae. Mangelsdorf (1948) states that the fruit case 
of teosinte (/uchlaena) ‘‘comprises an indurated glume 
of restricted proportions plus an indurated rachis-segment 
{internode] which internally is concave and partly sur- 
rounds the caryopsis.’” Mangelsdorf also uses the term 
fruit case to refer to the floral bracts alone when the 
rachis-segment is reduced to a mere appendage, as in 
tunicate teosinte. 
Fruir Cases IN THE AMERICAN Maydeae 
Maize. The floral bracts which usually form the fruit 
case in other grasses are of such reduced proportions in 
modern maize that they are completely obscured by the 
grain on a mature, well-filled ear. In the early stages of 
development, however, the ovary and even the young 
caryopsis is usually enclosed by floral bracts; the pistil- 
late spikelets are paired and each pair is associated with 
a cupule (Plate LV, figs. 1 and 2). This combination of 
structures is arranged about a ridged rachis in several 
longitudinal rows in which the cupules for one row of 
paired spikelets alternate with those of adjoining paired 
spikelets on either side (Plate LV, fig. 3). The entire 
polystichous structure which bears hundreds of exposed 
caryopses is enclosed and protected by numerous large 
spathes borne below on the shank. Although this pro- 
tective device in modern maize prevents natural dissem- 
ination, it is ideally adapted for harvesting by hand. 
Teosinte and Tripsacum. 'The fruit cases of teosinte 
and T'ripsacum are small, highly lignified, box-like struc- 
tures which occur in two alternating ranks. They are 
formed largely by what at first appear to be deeply hol- 
lowed rachis-segments. The openings of these ‘‘hollow 
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