251 
and its threadlike prolongation; it could be nothing but the tentacle 
and its base. It was then also found that the tentacle was not 
placed in the cavity of the funnel itself, but in a separate narrow 
channel at the inner side of the funnel, the tentacle-sheath. 
Sections further showed the tentacle to be provided at its surface 
with colloblasts (lasso-cells), a structure eminently characteristic of 
the Ctenopkora. The tentacles are unbranched. 
Another faet at once becoming clear after the Ctenophoran 
nature of the animal had been made out, was the median pore on 
the upper side; it is the pore leading to the statocyst. But the 
four pairs of knobs along the upper side of the animal? Nothing 
in the typical structure of Ctenophores could give the immediate 
explanation of them. Sections, however, soon revealed their 
nature — they are the genital organs, consisting each of two 
parts, one representing the ovary, the other the testis. The im- 
portant faet was also found through the sections, that they open 
to the exterior each through a duet, as is otherwise known among 
Ctenophores alone in Ctenoplana. 
That the branching canals in the walls of the body belong 
to the vascular system, could not be doubtful — but what was 
the morphological explanation of the two funnels? The develop- 
mental stages gave the clue to the question. In the young Cy- 
dippe-stages there is no trace of the funnels, but there is a deep 
furrow on the oral side, in the transverse (tentacular) plane; in 
the bottom of this furrow is the mouth - opening. The furrow 
gradually extends upwards along the sides of the body, so as to 
include the opening of the tentacle sheath. At this stage the 
young Ctenophore leaves its lodge in the parent animal and after 
a probably very short free swimming period fixes itself to the 
Umbelluta with the side-lobes of the furrow, the furrow then be¬ 
coming the basal surface, in the middle of which the mouth- 
opening is placed. The mouth is then, in faet, closed and the 
animal, not being parasitic, has to arrange itself in some way so 
as to get an opening which can perform the normal duties of the 
17* 
