100 ERYTHEA. 
C. ambrosioides, L. Less common than the last. 
Urtica urens, L. Notinfrequentin moist shady situations. 
Ricinus communis, L. In the waste ground and moist 
banks along the edge of ditches it has become well estab- 
lished and is a flourishing tree. 
Cyperus esculentus, L. I gathered a few specimens on 
the sand banks of the river opposite the Park in the autumn 
of 1891, which were so identified by Mr. J. N. Rose. Since 
then I have failed to discover it. 
Panicum sanguinale, L. Common in moist places, spread- 
ing readily by rooting at the lower nodes. P. Crus-galli, L., 
almost confined to damp and irrigated grounds, is very 
variable in height, form and pubescence. In the city streets 
I occasionally see a few isolated plants of P. colonum. 
The Botany of the State Survey gives San Diego Co., Arizona 
and New Mexico as localities where this is indigenous. With 
us the plants are so few, and apparently so strictly limited to 
the more favorable ground in the streets and lawns, that I 
think it may reasonably be classed among introduced species 
in this section. 
Setaria glauca, Beauv. A somewhat rare casual in the 
city streets. S. caudata, R.& 8S. Along the orchard fences 
on East Washington Street patches of this grass are 
flourishing. The vigorous growth would indicate that the 
species has been established here for at least a few years; 
but hitherto it has not been recorded from Southern California. 
Phleum pratense, L. Though not cultivated in the County 
it was once observed on the railroad at Elysian Park. 
Phalaris Canariensis, L. A casual on rubbish heaps and 
waste grounds. 
Polypogon Monspeliensis, Desf. Very common in the 
valleys and moister soils. 
Cynodon Dactylon, Pers. Chiefly in lawns, where once 
established it spreads rapidly, soon exterminating all other 
grasses. By some individuals it is preferred to any other 
lawn grass, requiring less watering and trimming, and form- 
ing if a less green at least a denser covering. In every 
