120 BULLETIN OF THE 
any pores for the egress of eggs, such as exist in the bursa of Ophiurans, 
It is therefore probable that the membrane ruptures at the breeding 
season, and the eggs are poured into the radiating compartments of the 
body-cavity. Here the sea-water might bring in spermatozoa for im- 
pregnation, after which the eggs of any compartment could be dis- 
charged through any one of tho ten genital openings. 
The chief difference between these organs in Gorgonocephalus and 
among Ophiurans is the greater specialization in the latter, where the 
lining membrane of the disk-wall becomes free, and enlarges opposite 
each genital opening into a closed pouch (bursa), whioh is extended in 
the form of finger-like tubes (ovarial tubes). In other words, the lining 
membrane, instead of being pierced by the genital opening, is continu- 
ous and simply becomes free and voluminous. In Gorgonocephalus, on 
the contrary, the genital opening pierces not only the disk-wall, but its 
lining membrane, and enters the body-cavity, while nearly the whole of 
the lining membrane takes on the egg-bearing function, and by the 
growth of the eggs is gradually stretehed and thrown into folded 
lobes. 
A section of a Euryale (Fig. 5) will show the different aspect of a 
non-gravid individual, whose stomach pouches are nearly empty, instead 
of being stuffed with the clotted substance already mentioned. Above 
is scen the stomach, which, on the right and left, passes into pouches, 
SU; and similar partitions, forming pouches, may be seen on the farther 
side of the centre. Above the lateral pouches are the radial shields, /, 4, 
cut through. On the extreme right and left are ercatly dilated genital 
openings, n o, which lead directly into the body-cavity ; and this, passing 
under and outside the stomach, is connected, about the mouth, by the 
perihæmal canal, a cross-cut of which appears at 8f. A section of the 
disk-skin, above the body-cavity, exhibited a uniform, tough, slightly 
fibrous texture, with a thin lining membrane, not well defined, and of a 
granular texture under a high power indicating perhaps egg-cells. Of 
fully formed eggs, however, there were none, and the lining membrane 
was not thrown into lobes or convolutions. If, however, the ovaries 
were distended and the stomach-pouches filled with matter, the general 
appearance would approach that of Gorgonocephalus, except that the 
stomach-pouches would be simpler; and the ovaries would be much 
more restricted in area, unless indeed the lining membrane of the body- 
cavity to which the stomach-wall adheres has the power to develop égg- 
clusters, and thus form lobes, and push the stomach inward towards the 
mouth. 
