A, Honey-gland from attractive C, Transverse section of the surface of lid.
If the coenosteum of Millepora be broken across, each pore-canal (perhaps better termed a polypcanal) is seen to be interrupted by a series of transverse partitions, representing successive periods of growth with separation from the underlying dead portions.
E, Transverse sec- r.c. Radial canal.
Across the arc is a transverse or radial magnetic field, and the electrodes are connected by an oscillatory circuit consisting of a condenser and inductance.
An important property is: the difference of the focal distances of any point on the curve equals the transverse axis.