MUSEUM OF COMPARATIVE ZOOLOGY, 249 
widening towards the oblique orifice ; the outer portion of the margin cut into 
five rather shallow teeth, intrathecal ridge strong and continuous with one 
across the stem of the branch. Nematophores are found in connection with 
the hydrotheca, and upon the stems ; supra-calycine nematophores very large 
and prominent, stretching far beyond the edges of the hydrotheca, orifice ter- 
minal and continued laterally on the inner side towards the pinna ; mesial 
nematophore large and strong, extending above the edge of the hydrotheca, 
adnate throughout, orifice like those of the supra-calycine nematophores ; cau- 
line nematophores quite variable in form, two on each internode, more or less 
triangular, with rounded or with one of the upper corners greatly produced, 
tapering towards the base; external orifice very large, extending entirely across 
the upper margin and into the lateral processes, when the latter exist ; the 
opening from the cavity of the nematophore into the stem is also very large, 
often being equal in size to the internal orifice of the hydrothecæ. At the base 
of each pinna, in a direct line with the hydrothece, is an oval swollen process, 
with a small circular orifice on the upper surface near the proximal end ; its 
cavity is directly continuous with that of the hydrotheca in front of it, and 
also with that of the stem. 
Gonosome. — Unknown. 
Localities. — Ten miles north of Zoblos Island. Lat. 24° 8/ N., Long. 82° 
51/ W. Depth, 339 fathoms. 
The most prominent feature of this interesting species is the great develop- 
ment of the nematophores. Those in connection with the hydrothees are 
above the average size, and those of the stems are among the largest known ; 
the peculiar processes borne on the bases of the pinne may also perform the 
funetions of nematophores, but until live specimens have been examined it 
will be impossible to say. Of the two cauline nematophores found upon each 
internode the proximal one has always the more regular outline, owing prob- 
ably to the fact that on this portion of the internodes there is an abundance 
of room for them to develop in every direction, while those situated on 
the distal end are limited in their growth in one direction by the basal pro- 
cesses of the pinna, This will readily be seen by reference to the figure. It 
is also worthy of notice that the corner of the distal cauline nematophore 
which is most strongly produced is the one on the opposite side to the base of 
the pinna. By stretching out in this direction it reaches a freer space in which 
to manipulate the protoplasmic processes which it may send forth. 
The ecnosare of the most proximal hydrotheca on each pinna finds its way 
to the coenosare of the main stem by passing directly through the cavity of the 
oval basal process, and from the size of the opening of the basal process I im- 
agine that it must be used for the protrusion of protoplasmic processes like 
those from an ordinary nematophore. The process differs, however, from the 
ordinary nematophores in containing a portion of true coonosare, and to this 
extent it approaches the nature of a hydrotheca ; that is, there exists a swollen, 
oval process of the perisarc, containing a process of the cœnosarc, and with 
(what in all probability is) a mesial nematophore upon its upper surface. It 
