82 
Proceedings of Boyal Society o f Edinburgh. [sess. 
each other by a considerable interval, but are still connected together 
by axial prolongations of their coelentera. This arrangement may 
he indicated in the following manner : — 
fT\ 
fR\_ 
r ^ 
In Bathypatkes the isolation of the dimorphic zooids, each hear- 
ing a pair of tentacles, might lead one to suggest quite a different 
interpretation if the intermediate steps in the differentiation were 
not known. It will, however, he evident from the points already 
indicated in outline, that the dimorphism in Antipathidse is brought 
about — firstly, by an elongation of the zooid in the transverse axis ; 
and, secondly, by the formation of two vertical constrictions and 
mesogloeal partitions by which the elongated zooid is divided into 
three portions, one nutritive and two reproductive. These in 
Bathypatkes are frequently more isolated than are the unmodified 
zooids of normal types, and have as much claim to rank as indi- 
viduals. 
I have thus been led to divide the family Antipathidse into two 
sub-families, of which the following short diagnoses will serve our 
immediate purpose : — 
ANTIPATHIDiE. 
1 . Antipathince. — Zooids of the normal hextentaculate type, show- 
ing a tendency to become elongated in the transverse axis, which 
corresponds to the axis of the supporting skeleton. Examples 
— Leiopathes, Girripathes , Antipathes , Parantipatlies , &c. 
2, Schizopathince . — Zooids dimorphic and bitentaculate, of which 
three — viz., two gonozooids and one gastrozooid — are morpho- 
logically equivalent to one unmodified zooid of the normal 
type. Examples — Schizopathes , Bathypatkes, &c. 
In this connection the genus Parantipatlies forms an interesting 
link between the two sub-families, and shows clearly the mode by 
which the dimorphism has been produced. 
