210 IOWA STUDIES IN NATURAL HISTORY 
shells dredged from a depth of eighteen to twenty-four fathoms. 
One of these has an oblong corallum resembling a small Fungia 
measuring one and three-eighths inches long and a little more than 
half an inch in width. It doubtless belongs to the genus Flabel- 
lum. The septa seem to be in four series and the corallum is un- 
usually deep. It came from off Colville Island and is the largest 
single corallite in the collection. 
Another form was rather profusely branched and bore some 
resemblance to an Oculina, one of the true reef corals. The in- 
dividual corallites are tubular with cireular apertures and no 
evident costw. They are about four mm. in diameter and the 
colony consists of a dense clump of slightly separated corallites 
resembling Dendrophyllia manni Verrill as illustrated by Vaughan 
in his work on Hawaiian Corals. But our specimens have no 
cost. 
A very delicate, branching, white hydrocoralline was also 
brought up in the trawl. The gastropores form perfectly round 
holes in the surface of the branches but near the tips they are 
cut obliquely and the margin is exserted on the outer side form- 
ing a sort of scoop-like projection. 
There are several interesting things among the hydroids and 
it is evident that a thorough exploration of Hauraki Gulf would 
yield important results in this group. The following may be 
mentioned as occurring in our collection: 
Halectum robustwm Allman. This species has a thick, fascicled 
stem and sessile hydrophores and was taken by the Challenger off 
Cumberland Bay, Kerguelen Island, from a depth of 105 fathoms. 
Curiously enough I found it in the material of the Harriman 
Alaska Expedition and gave it the same name, as a new species, 
overlooking its apparent identity with the form described by 
Allman. 
Synthecium, sp.. A specimen from off Cape Colville shows the 
gracefully recurved and finely rimmed hydrothece characteristic 
of this genus, which was originally described by Allman from 
specimens from New Zealand, although it has since been reported 
from various other parts of the world. 
Sertularella. A species of this widely distributed genus is from 
the same locality as the last. The hydrothece are tridentate, the 
teeth low, inconspicuous, and large. The gonangia are character- 
istic of the genus being very evenly corrugated like Japanese 
