84 IOWA STUDIES IN NATURAL HISTORY 
ification. Such spicules are found in Sarcophyton belonging to 
the Aleyonide, according to Thomson. and MeKinnon.*% 
In longitudinal section the canals are parallel but branch near 
the surface to connect with the numerous polyps and are almost 
filled with ova which are often found a considerable distance be- 
low the surface. The partitions between. the canals bear numer- 
ous spicules, which would indicate that the species belongs to the 
sub-family Siphonogorgine; but I find no report of double-stars 
in this group. <A eross section of a branch shows no large central 
canal or group of canals but the walls are thicker than usual, 
probably from the necessity of accommodating the muscular masses 
that effect the retraction of the branches. In a retracted colony 
such a cross section shows the water tubes occupied by tissue 
which seems continuous with the polyps and may be muscular. 
Another aleyonarian found aboundantly on Makuluva flats be- 
longs to a family that I have not met with before, the Xeniide. 
The colony is encrusting or irregularly lobate, a clear reddish 
gray, almost violet, in color and lives in the shallower tide pools 
of the flats. Often the bodies of the polyps are almost white and 
the tentacles gray. In some eases the polyps are entirely white. 
They are non-retractile, a characteristic of this family, hence this 
form is an admirable one to preserve for class use. The polyp 
bodies are translucent and about one-half inch long in the living 
specimens. The tentacles are strong and have a close-set fringe 
of stubby papille on either side, with two or more rows on each 
side of a tentacle. In certain views the papille appear to cover 
the upper surfaces giving the appearance of closely set knobs. 
The tentacles and papille are frosted over with numerous minute 
spicules which are round or oval disks with a granulated appear- 
ance, and shaped like red blood-corpuscles. These spicules are 
also numerous on the thin polyp walls where they are closely and 
evenly scattered. These disk-like spicules are also characteristic 
of the family Xeniide. Although they are most abundant on the 
surface, some of them are seen scattered throughout the fleshy 
cenemchyma. The polyps are so packed together on the surface 
as to leave very little room between their bases. 
A longitudinal section of a branch or lobe shows the numerous 
canals which are continuous with the body cavities of the polyps 
ira a on the Perey Sladen Trust Expedition to the Indian Ocean, pl. 
ecto alee 
