PANICE/fi. 



161 



barbed bristles above the base; lieads 5-6 mfti. long, beside the 

 Bi»ines, containing 3-5 sjiikelets. Spikelets ovate-laneeolate. 5 mm. 

 long, llrst ghime 4: mm. long, 5-nerved, second like it only a little 

 sliorter; palea 5 mm. long, 2-nerved, containing 3 stamens; fertile 

 floret ovate-lanceolate, acuminate, 4 nmi. long or more. 



•' N'ariable in the length of the spike, the size of the spikelets. the 

 length of the lowest glume, the number of glume-nerves, and in the 

 development of the palea in staminate or 

 neutral flower." Grisebach's Flora of 

 the West Indies. 



North Carolina to Florida and Texas, 

 West Indies, Mexico to Brazil, tropical 

 Africa, East Indies. 



4. C. tribuloides L. Sp. PI. 1050 

 (1753). Bur-grass. Sand-kur. Hedge- 

 noG-GRASS. C. Caroliniamis Walt. Fl. 

 Car. 79 (1788). 



A branched ascending annual, 30-00 

 cm. high. Sheaths loose, about as long 

 as the internodes; ligule ciliate: blades 

 linear, flat or condiiplicate, about 10 cm. 

 long, 5 mm. wide. 8i)ike usually oblong, 

 with G-'iO spherical heads about G mm. 

 long, besides the spreading barbed spines; 

 heads more or less downy. Spikelets '2-3 

 in each head, ovate, 5-7 mm. long, first 

 and second glumes subequal, 5-nerved 

 and 3-nerved respectively, third glume 

 (palea of the neuter floret) hyaline, 2- 

 nerved ; fertile floret ovate, briefly acu- 

 minate, about 5 mm, long. 



New Jersey, V. S. Depf. Agricul. Fig. 2d.—Cendtorus tribuloi- 

 Vl-l, identified by Vasey and Scribner; b,\ixme iii^^'it'ctiou-' \', 

 Michigan, Conhy; Illinois, Beal 25. spikelet. (Scribner.) 



Number 341*, of Dr. E. Palmer, Souora, Mexico, is a more 

 .slender plant, the heads scarcely more than half the size of 



