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other species. The cuticle (c) and cell wall, are well developed in 
this species. The leaf is strongly involute on the upper sur- 
face and here we also find papillae. 
The bulliform cells (b) are also much larger than in the 
other species, there being four to six in a row, sometimes one 
large central cell and sometimes two large central cells with two 
smaller bulliform cells on either side of the large ones. 
The carene (c), in this species consists of five mestome 
bundles (m), three very small, a large central, and one medium 
in size. The leptome (1) and hadrome(h) are fully developed in 
the two large bundles. The hadrome is separated from the 
leptome by two layers of thick walled parenchyma. One small 
mestome bundle occurs on each side of the medium bundle. 
The mestome bundles are all connected with each other by 
the mesophyll (m). 
The mestome bundles number thirty- eight, eighteen on 
left and twenty on right side of carene (c). In this species three 
types of bundles occur: First, those open on both sides;, 
second, those open above only; and third, those entirely closed. 
Those of the third type are of two sizes one very small, the 
other somewhat larger. The mestome bundles of the third 
type predominate. The sides of the leaf terminate with a 
closed bundle. In the mestome bundle of the second type the 
leptome and hadrome seem to be in immediate contact with 
each other, but in those of the first type they are separated 
by thick-walled parenchyma. The chlorophyll bearing paren- 
chyma does not differ materially from that found in other 
species. 
The stereome (st) is on the lower side of all the bundles and on 
the upper side of those of the first and second type. The leaf 
also terminates with irregular groups of stereome. The ste- 
reome is quite well developed in the carene where it occurs 
in large groups. 
The mesophyll (mes) in this species connects the different 
mestome bundles and consists of both round and elongated 
cells. 
The uncolored parenchyma is more strongly developed in 
this than in any of the other species of Sporobolus studied. It is 
prominent in the midrib, where it occupies the space above the 
five mestome bundles. It also occurs immediately below the 
bulliform cells and on the upper side of the mestome bundles 
