AMERICAN 
JOURNAL OF SCIENCE AND ARTS. 
[SECOND SERIES.] 
Arr. L—On Zoiphytes, No. 111; by James D. Dana.* 
26. In our preceding chapter on Zodphytes we briefly noticed 
the characteristics of the Hydroidea, one of the two grand di- 
visions of these animals. A digestive cavity, a mouth, and a cir- 
cle of fleshy arms or tentacles around the mouth, were mentioned 
as the sum-total of many of these simple organisms. Fixed in 
general to some support, they eat, and grow, and bud out their 
young as plants their flowers and leaves. i Thus they form the 
fine feathery fronds and moss-like tufts so common among these 
lower polyps, and whose branchlets are made up of minute flower 
animals in place of leaflets, exquisite in beauty and arrangement. 
They have delicate horny or membranous coralla when any at 
all, and take little part in the formation of reefs. 
Order If. ActrnorpEa. 
The next order to which we now pass, comprises all the ordi- 
nary coral zoéphytes, the branching and foliate Madrepores, the 
massive Astreeas and Meandrinas, the slender sea fan, and also the 
common Actinia. Among them are flowers of all hues and sizes. 
The Actinie may well be called the Asters, Carnations, and 
* Abstract of the Exploring Expedition — on Zoophytes by the writer; 
continued from vol. ii of this Journal; see p- for No. I, and p. 187 for No. IL 
a-Anemone is the common name. 
Seconp Senres, Vol. Ill, No. 7.—Jan., 1847. 1 
