358 



CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



cleft and bearing 2 short awns; palet and upper floret smooth; behind the palet of 

 the upper floret, a short awn, 1 mm. long, the prolongation of the rachilla; caryopsis 

 not seen. (Figure 21.) 



The species has not often been collected. In the U. S. National Herbarium, Prin- 

 gle 2559, 11242, 5398, and Palmer 200, all from the State of Jalisco, Mexico, are repre- 

 sentative. Palmer has also collected it near Durango, Mexico. Rose's no. 1621, 

 Sinaloa, and Rose & Hough 4775, Jalisco, are typical. 



Fig. 22. — Cathestecum prostratum. a, Sheath with inflorescence protruding, 6howing two 

 spikes, one with 3 spikelets, the other with the lower pair of spikelets aborted; b, up- 

 permost spikelet; c, d, lemma and palet of first floret; c,f, lemma and palet of second 

 floret; g, h, lemma and palet of third floret; i, lemma of fourth floret; j, one of lower 

 pair of spikelets; fc, I, lemma and palet of first floret; m, n, lemma and palet of second 

 floret, a, Scale 5; b-n, scale 7.5. Fr m type specimen. 



CATHESTECUM Presl. 



Cathestecum Presl, Rel. Haenk. 1 : 294. pi. 42- 1830. Based upon C. prostratum. 

 Bentham and Hooker write the name "Cathestechum." 



Inflorescence racemose, with 4 to many spikes, each consisting of 3 approximate 

 spikelets, the first glume of each spikelet, or at least of the terminal one, more or less 

 reduced, commonly to a nerveless fimbriate scale, the lemmas of the upper florets 

 showing a tendency toward branching, or sometimes an actual multiplication of 

 nerves and awns by division of the typical lateral nerves. 



« Gen. PI. 3: 1122. 1883. 



