SPIKELETS WITH HARDENED FRUITS 73 



the spikelets attached. (Recall Lepturus, Lesson V, 

 Fig. 28, page 37.) 



In Syntherisma, Paspalum, Reimarochloa, and 

 Stenotaphrum, with subsessile spikelets borne on one 

 side of a rachis, the spikelets 

 are placed with the back of the 

 fertile lemma against the rachis, 

 that is, with the first glume 

 (developed or hypothetical), 

 sterile lemma, and the palea of 

 the fertile floret outward. In 

 Axonopus (Fig. 65), Brachiaria, 

 and Eriochloa the spikelets are 

 reversed, the back of the fertile 

 lemma being turned from the 

 rachis and the palea toward 

 it. In Axonopus the first glume 

 is wholly suppressed. In Erio- 

 chloa (Fig. 66) the first glume J 



is reduced 



to a m i- 



nute sheath 



around the 



enlarged rachilla joint below the 



second glume and grown fast to it. 



The fertile lemma is tipped with 



a minute awn, which breaks off 



readily. 



Fig. 66. A, spikeiet of In bamyard-grass, Echinochloa 

 B^fertUe i^X^^"' CrusgalU, is the same type of spike- 



FiG. 65. A, part of raceme 

 of Axonopus furcatus; B, 

 inflorescence; C, cross- 

 section of rachis. 



