Bys Walks Round San Francisco. 780 
neighborhood. The first of these attains a large size, the test or 
shell, denuded of its long spines, measuring five inches or more 
in diameter ; the second has short spines, and is about two inches 
across. These are “regular sea-urchins,” that is to say, they 
belong to that sub-order of the Echini which has circular, high, 
sometimes almost globular tests, with the five ambulacral areas at 
equal distances and of equal dimensions, pierced with rows of 
pores continuous from the mouth below to the apical system above, 
which latter contains not only the “ ocular” and “ genital ” plates, 
but also the posterior termination of the digestive canal. The 
cake-urchin before mentioned, like all its near relatives, has the 
anus on the under side, thus departing farther from the “ radiate ” 
type, and the rows of ambulacral pores for the exit of the suckers 
are confined to the upper side of the test. 
Along the upper portion of the sandy beach, at points where 
there are no cliffs but where the land meets the sea in rolling 
ridges of sand, may be found several plants which do not occur 
in other situations. Among these are Frinseria chamissonis and 
F. bipinnatifida, two composite with inconspicuous flowers and 
hispid fruits, covering large areas with their trailing stems and 
glaucous foliage; Adronia cycloptera, a relative of the garden 
flower commonly called four-o’clock, with its upright bunches of 
sweet-scented reddish flowers; Heliotropium curassavicum, one of 
the Boraginacee, with curled-up spikes of small white flowers, 
and thick leaves, and the yellow-flowered Ænothera cheiran- 
thifolia. 
On the cliffs near by, ‘Sedum spathulifolium makes a show with 
its bunches of yellow flowers, mingled, perhaps, where the soil is 
deeper, with Aster chamissonis and the golden-rod, Solidago califor- 
nicum. Here is a large area of cliff face covered with the long trail- 
ing stems of Mesembryanthemum dimidiatum, the three sided oblong 
leaves glistening in the sun,and the large deep-purple flowers glow- 
ing at intervals like rubies. It is the monarch of the sea-side flowers, 
and is worthy of a place in the flower-garden, but must not be 
planted in too rich soil, or it will run to stems and leaves, and 
forget to bloom. 
On the hill-sides the most conspicuous plant is the “ bladder- 
weed,” Astragalus menziesii, not in bloom now save a few belated 
blossoms, but hung .all over with the bladder-like pods from 
which its vernacular title is derived. The seeds in the ripe pods 
