MEDUSA. 41 
into a very broad adhesive disc, by which the animal fixes itself to the bottom of the 
sea. There is no true stalk, and only a narrow constriction separates the umbrella 
from the adhesive disc. The peduncle is hollow and consists of one single chamber, 
which is partly filled up with the bulbous enlargements of the four teniole. The 
internal longitudinal muscle bands of the teniola terminate at the constriction, and 
do not proceed into the peduncle itself. In the peduncle the teniole are wholly 
gelatinous, as in Lucernaria campanulata. The jelly or mesoglea on the bottom of the 
peduncle and of the teeniola is permeated by small branched canals which come from 
the hollow chamber. The ectodermal surface of the peduncle is divided up into 
numerous small lobes and irregular folds, which are flattened out on the side used 
for attachment. 
The mouth has a large, thin, leaf-like margin which is beautifully arranged in folds. 
It opens through a small constricted cesophagus into the stomach, which is rather 
small for the size of the umbrella, and is well packed with gastric filaments. The 
funnel cavities are large and penetrate about half the length of the stomach. The 
gastric filaments are very much crowded together on the teniole. As a rule they are 
branched close to their base, and occasionally near their distal ends. They have the 
appearance of flat slender ribbons, about 5 to 10 mm. in length. 
The arms are short and thick, and are about equal distances apart. Upon each 
arm is situated a large oval cluster of short capitate tentacles, the number of which is 
estimated up to about three hundred. The capitate apex of the tentacle is crowded 
with long nematocysts. The tentacles forming the outer row, on the ex-umbrellar side, 
are provided with a lateral adhesive pad (Plate V., fig. 4), and some of the tentacles 
in the second row have also similar pads. Lucernaria campanulata has adhesive pads 
of similar structure on the tentacles occupying the same position as those of Lucernaria 
vanhoeffent. 
The gonads extend from the stomach to the base of the arms, forming fairly broad 
bands. Each band consists of a large number of elongated sacs (Plate V., fig. 5). 
Transverse and longitudinal sections were cut of the sacs, but only a diagram 
(Plate V., fig. 6) of their structure is given, as the preservation was too bad for the 
drawing of an actual section. Each sac consists of a large number of little branched 
or unbranched tubes, lined with endoderm and separated from one another by 
mesoglea. All the tubes are connected with a main duct, which runs the whole length 
of the sac and opens at one end to the exterior. The blind end of the tubes is blocked 
with cells, amongst which small ova are clearly visible. It is amongst these cells at 
the end of the tubes that the gonads develop, and when the ova reach a certain size 
they pass down the tubes into the main duct which opens into the gastric pouch. In 
the male the small tubes are not so well defined. There are masses of sperm mother- 
cells, which are connected with tubes leading into a large broad duct filled with 
spermatozoa. The structure of the gonads of Lucernaria vanhoeffent is similar to that 
described by Antipa for L. walters. 
