KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 51. N:o ll. 25 
thelia, ought not to be arranged and classified elsewhere. TI refer to such cases as are un- 
doubtedly nothing else than transformed species of Alcyontidae or Nephthyidae. (Com- 
pare p. 20.) 
In my diagnosis of Cornulariidae I have recorded the exclusive existence of spindles, 
rods, and clubs in the armature. In Cornularia the spicules do not exist and sometimes 
also they are absent from Anthelia. 
Different authors have found mostly other types of spicules within Clavularia and 
Anthelia (HICKSON, SCHENK), but it appears to me doubtful whether species provided with 
such spicules are in reality Cornularids. The membranous development of species outside 
Cornulariidae has not always been taken into consideration. Naturally, these spindles, 
rods, and clubs can be mixed with a few other types, but the principal armature consists 
of the types mentioned. TI have found this in the case of the northern Cornularids. 
Generally, the polyps within Clavularia and Anthelia are large and the large spindles, 
rods, and clubs are necessary to support the polyps. The retraction of the polyps in 
coenenchym is impossible in account of the poor development of coenenchym. It is to 
be observed that the first differentiation of spicules in polyps from the general type arises 
in the upper part of the polyps (Clavularia), which part can often be retracted in the 
lower polyp part. Spicules in this part are minor spindles and rods, but also types, 
which are found in genera of more developed families. The large spindles and rods 
and clubs are the typical spicules of Cornulariidae. 
On account of this I cannot refer Sympodium EHRENBERG to Cornulariidae. (Com- 
pare p. 19,32.) 
The most important characteristic relied upon by BRocH (1912) and KÖKENTHAL 
(1906) to determine the difference between Anthelia and Clavularia, viz. the existence of 
a calyx, does not always allow of a sufficiently sharp distinction between these genera. 
For, owing to the extreme variety, in most cases, in the shapes of the spicules and in their 
distribution within the polyps, the shape of the calyx, too, is extremely variable, so that, in 
some cases, it is practically impossible to decide whether a calyx is really developed or not. 
As regards the Anthelia, although the spicules are all of the same shape and size 
and are embedded within the body wall of the polyp over the whole of its length, still 
they cannot be said altogether to exclude the possibility of a retraction of the upper part 
of the polyp. 
In several specimens of Anthelia borealis (KOR. and DAN.), BRocH has observed a 
formation, called »pseudocalyx», which closely resembles the calyx. This proves that, 
amongst the Anthelia, too, there exists at least a tendency towards the same retraction 
which is common amongst the Clavularia, a fact which makes the existence of a calyx 
inadequate as a distinguishing feature. 
There are, however, pronounced differences, both in shape and size, between the 
spicules from the upper and the lower parts of the Clavularia polyps, whereas in an An- 
thelia polyp the spicules are all of the same type. This feature gives us a sufficiently sharp 
distinction between the members of the two genera, so that we are still entitled to regard 
them as separate genera. 
K. Sv. Vet. Akad. Handl. Band 531. N:o 11. + 
