KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 32. N:0 I. 65 



Heliolites fasciaiics n. 



Pl. IV, tigs. 20—25. 



3Iode of growtli. This species forms flat, discoid lamellae attaining at the highest 

 a thickness of 2.5 millimeters. The epitheca is finely striated by minute lines running 

 parallel with the lines of growth. 



The calides are circular or nearly so, sometimes with thick, indented theca, only 

 attaining 0,8 in diameter. The septa are thick, short, reaching only halfways to the centre 

 (pl. IV, fig. 21); in the centre a sinuous columella-like protuberance. In a longitndinal 

 section (f. 24) the septa are not visible. The irregularly distantiated tabulte are more or 

 less conoave, but well developed. The columellar streak is partly visible, being present 

 only at intervals. 



The most peculiar feature is the banded appearance of the longitndinal section, 

 some nine fascise, nearly parallel succeeding each other in a section (fig. 22). In fig. 23 

 a part of the coenenchyma is still more magnified. These fasciffi are a sort of compres- 

 sion or, as it were, a condensation of the tabulse, which have heaped themselves, so as to 

 be five or six on a distance of only 0,2 or 0,3 millim. while on the same distance else in 

 the section there are not more than one tabula. These bands have a white colour, in 

 transparent light black, whence they in the drawings also are black. Whatever raay have 

 caused this tightening of the coenenchyma at the same level along the whole polyparium 

 and at regular intervals, being oftener repeated, however, near the upper surface, it occurs 

 in all specimens which have been found of this coral and thus acquires the value of a 

 regularly occuring phenomenon during its growth. In these bands the tubuli have divided 

 more frequently than on both sides below and above. In a transverse section (fig. 25) 

 taken through a fascia, great irregularity reigns, the coenenchymal tubes having all sorts 

 of forms, the septa, three or four crossing the calicle in sinuous lines. 



This species has been found in several specimens in the Arachnophyllum-stratum 

 near Wisby and also at Westergarn. 



Heliolites repletus n. 

 Pl. IV, figs. 26—31, pl. v, flgs. 1, 2. 



Mode of growth. This corallum has grown in large disks or semiglobular masses. 



The calides have a size of 1,2 millims. and are perfectly circular when fuUy developed 

 having an indented, slightly exsert margin. 



The septa, threadfine and sinuous in a not fuHy developed calicle (fig. 28), are in 

 a mature calicle (fig. 29) sti-aight, stretching near to the centre, where a small protuberance 

 forms a sort of columella. It seems, to judge by the sections, that during the growth of 

 a calicular tube there may be septa present some time and then wanting. (Figs. 30 — 31, 

 pl. iv). This may coincide with changes nearly resembling those in Hel. fasciatus or with 

 a tightening of the coenenchyma so as to form horizontal fasciaä. The coenenchyma, which 



