366 Prof. P. M. Duncan on Prof. G. Lindstriém’s 
gical criticisms by giving the following interesting result of 
his examination of young specimens of Deltocyathus italicus * : 
—‘‘ In the smallest specimen I have seen, of only 0°7 millim., 
there are four septa of the first order, towards which two of 
the second order are growing, and with these again the smaller 
belonging to the third order unite. But to judge by a speci- 
men which is a little bigger (1°5 millim.) and has six regular 
septa of the first order, the law of substitution as expressed 
by Lacaze-Duthiers (Arch. de Zool. Expér. t. i. p. 868) 
comes into play; and of the six apparently primary septa 
four may have been developed out of secondary ones, only 
two of the original four resting in their original position as 
septa of the first order, the other two being, as it were, 
pushed aside and degraded into secondary ones.” Neverthe- 
less it must not be imagined that this arrangement is universal 
in the genus, for in the specimens in my possession the regu- 
larity of the appearance of six primaries and the succession of 
six secondaries is clear, and it is confirmed by the study of 
the coste. The term “ phenomenon of substitution” is 
much more correct than the term ‘ law.” 
5. Hlabellum laciniatum, Philippi, sp.—Lindstrém recog- 
nizes amongst the Josephine dredgings the common North- 
Atlantic Plabellum, which Sars had called Ulocyathus arcticus. 
But he confounds with it #labellum alabastrum, Moseley— 
a conclusion which is refuted by that author in his ‘ Report 
on the ‘ Challenger’ Corals,” with which I agree. 
6. Duncania barbadensis, Pourtalés.—Lindstrém makes 
some valuable remarks upon this species, and notices the 
sameness of the septa, except those which are in relation 
to pali. He states that the material which fills up the 
calice from its base is stereoplasma, or a secretion of the 
basal membrane superseding or supplementing the dissepi- 
ment. He gives the only comprehensible drawing of the 
calice we have, and states that he has found six septa near 
the base. I found in a Gwynia a tetrameral arrangement of 
septa above, but a hexameral one at the base. 
Pourtalés states that Haplophyliia, which comes close to 
Duncania, has the soft parts similar to this last. At present 
these genera, I consider, must be associated with Gwynia, 
nobis, in a group in the Turbinolide, and not with the 
Rugosa. 
7. Schizocyathus fissilis, Pourtalés.—Lindstrém obtained 
the specimens he described from Anguilla, Salt Island, and 
the Josephine Bank, in from 200 to 790 fathoms. He 
describes an epitheca, which is not to be distinguished from 
* Op. ct. poll. 
