HYDROZOA. 
47 
stems giving off whorls of slender branchlets bearing the minute cups Case 3b. 
and still more minute funnel-shaped nematophores. 
A. ramosa (Case 3b) has branched stems. 
In Aglaophenia pluma, the “Podded Coralline,” the reproductive 
capsules are protected by a pod-shaped receptacle formed by modified 
branchlets which curve round and meet. 
Aglaophenia mens* from Java, is named on account of its severe 
stinging properties. Some species of this genus living in the tropics 
attain a height of several feet, and it is dangerous to come in contact 
with them. 
Fig. 8. 
II. HYDROCORALLINiE OR CORAL-LIKE HYDROZOA. 
The Hydrozoa of this group resemble the Reef Corals in forming Cases 2, 4. 
a calcareous skeleton ; indeed, the Hydrocorallinse were supposed 
to belong to the same class (Anthozoa) as the Corals, till Agassiz 
showed that Millepora was a true Hydrozoon. Later, Moseley, in his 
classical work on the Challenger Hydrocorallinae, confirmed Agassiz’ 
results, and proved that the Stylasteridce were also Hydrozoa. In 
all the Hydrocorallines two forms of polpys (Eig. 16 ) occur, viz., 
gastrozooids, with mouth and stomach, and tentacle-like dactylo- 
zooids without a mouth ; the gastrozooids are contained in pits 
