KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 51. N:o |l. 21 
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of the membranous transformations being much more vigorous and more extended is 
the more plentiful supply of coenenchym. 
If we once more summarize the differences between the Cornulariidae and the 
membranous forms, we find: 
Cornulariidae: Membranous forms: 
1) Coenenchym inconsiderable. 1) Coenenchym vigorous. 
2) Polyps free, connected only at the hase. 2) Polyps surrounded by the coenenchym. 
3) Mesogloea with a few canals. 3) Mesogloea with numerous canals and 
anastomosis strongly developed between 
these. 
4) No vertical canals occur. 4) In addition to horizontal canals, vertical 
canals. 
5) The form of spicules: rods and spindles. 3) The form of spicules: spindles, rods, 
rollers, crosses, dumb-bells, etc. 
6) Total retraction of polyps does not occur. 6) Total retraction of polyps (anthocodiae) 
may occur. 
Relationship within Alcyonacea. 
If we do not take in consideration the fam. Haimeridae, the most primitive family 
within Aleyonacea is the Cornulariidae. 
Cornularia, whose polyps are supported by a horny secretion, and lack calca- 
reous spicules, is the most primitive genus. The stolons consist of simple cavities. 
The development within the family is continued with Anthelia. Calcareous spicules 
exist in the polyp body and in the walls of stolons, and they consist of spicules, rods and 
clubs. These are of the same shape and size in the upper and lower parts of the polyps- 
Stolons contain a number of shorter endodermal canals or cell-strings. Clavularia is dis- 
tinguished from Anthelia by a differentiation in shape and size between spicules of the upper 
and lower parts of the polyps (p. 26). KÖKENTHAL (1906) proposes as a distinguishing 
characteristic between Anthelia and Clavularia the existence of a calyx (kelch) within 
Clavularia. A calyx also may occur within Anthelia (p. 26). A retraction of the whole 
polyp is impossible both within Anthelia and Clavularia, in consequence of the unimpor- 
tant coenenchym in stolons and the well-developed spicules in the polyps. The upper part 
of the polyp can be retracted in the lower one. The differences between the spicules of 
polyps within Clavularia prove a more developed stage. Within both Anthelia and 
Clavularia we meet with membraneous forms. (We must except the membranous forms 
which belong to other families, but have been considered as Cornularids.) The genus 
Sympodium may be excluded from Cornulariidae. 
From this family the evolution has proceed to Alcyoniidae. "The agreement be- 
tween the shape and distribution of spicules in anthocodiae and colonies is sufficient to 
