193 
m, 3 ex.; Stat. 53, 85 m, 2 ex.;) Banda, ofT Neira, ca. 20 m, 2 ex.; (Banda, 
off Selamo, ca. 70 m, 1 ex.; off Samalona, near Macasser, 15—20 m, 1 ex.; 
Stat. 99, 25 m, 4 ex.) 
Koh Mesan, Siam, 27 m, 3 ex. Dr. Mortensen leg. 1900; North of 
Koh Kahdat, Siam, 7—9 m, 3 ex. Dr. Mortensen leg. 1900. 
Dr. Morte nscn’s Pacific Exp.: Honolulii, 18—72 m, 3 ex. 
Diaseris-spQCimens: 
D. Exp. t. Kei Isl.: (Stat. 10, 50 m, 3 fragmentsV, Stat. 19, 20 m, 1 frgm.; 
(Stat. 24, 100 m, 2 frgm.; Stat. 25, 85 m, 1 frgm.; Stat. 53, 85 m, 3 frgm.; 
Banda, off Lontor, 14 m, 57 frgm.; (Banda. various localities, 70—100 m, 4(3 
frgm.; off Samalona, near Macasser, 15—20 m, 3 frgm.;) Stat. 65, 25 m, 8 
frgm.; Stat. 82, 35 m, 4 frgm.; (Stat. 106, 32 m, 2 frgm.; Stat. 116, 22 m, 
1 frgm ^ 
North of Koh Kahdat, Siam, 7—9 m, 7 frgm.. Dr. Mortensen leg. 1900. 
Dr. Mortensen’s Pacific Exp.: Jolo, Sulu Islands, ca. 45 m, 1 frgm.; 
(Honolulu, 18—72 m, 3 frgm.) 
In the young stages of this species the hexagonal shape of the 
corallum is less pronounced than in F. hexagonaliSy though the 
septa of the lower cycles are much higher than those of the 
higher cycles. 
In specimens preserved in alcohol the different cycles of ten- 
tacles are often clearly to be distinguished; a very typical example 
showing this arrangement is represented in fig. 13. 
When broken, the Cycloseris-specimQns of F. patelliformis usually 
regenerate to a circular form which shows some irregularities in the 
course of the septa. Here the regenerated part does not grow out 
as wedge-shaped sectors separated by grooves, as in Diaseris-^orms. 
Therefore the two different forms of growth in F. patelliformis, the 
Cycloseris-and the D/asens-forms, are not so closely connected as 
it would seem at first sight. One would expect that fragments of 
a Cycloseris-foTm would give rise to the formation of Diaseris- 
specimens, but in my material the great majority of these broken 
Cycloseris-specimQns are regenerated into more or less complete 
Cycloseris-forms. Besides these there are a number of intermediate 
stages, regenerated coralla, which are no true Cycloseris-speclmens, 
and neither have the pronounced characteristics of the Diaseris- 
form. Some specimens illustrating this kind of regeneration I have 
already described in my former paper (1923 c) on the species of 
the pateild-group. The short description in the following pages of 
some more regenerated specimens of F. patelliformis will show that 
Yidensk. Medd. fra Dansk naturh. Foren. Bd. 79. 13 
