KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 32. N:0 I. 63 



Heliolites farvistella, var. intricata n. 

 Pl. IV, figs. 10—19, pl. v, fig. 3. 



Mode of growth. The corallum is arbovescent or tuberous and there is scarcely any 

 epitheca seen. 



The calides are, when fully developed, nearly circular with lobate edge through 

 the indentations in the wall opposite the septa and very thin. The twelve threadfine 

 septa are sinuous, some coalescing before they reach the centre of the calicle where they 

 all join in an irregular net. The tabulas are, as in the former, much broken up and liemmed 

 in between the septal laminse. 



The coenenchyuial tubuli vary much; they are regularly polyedric or they are of 

 very dififerent size (pl. iv, f. 11, 13, 14) raany of them with small ribs or costa^ shooting 

 out into the tube (pl. iv, f. 11). They may also be inucb irregular, assuming all sorts 

 of shapes (pl. iv, f. 13), meandring and curved. 



Propagation. The coenenchyraal gemmation may be observed on the surface of the 

 polyparia as well as through transverse sections deep below the surface. Fig. 11, pl. iv 

 represents the gemmation on the surface. It begins at first as a little shallow dimple pl. v, 

 f. 3 all över covered by the meshes of the coenenchyma. In proportion as this shallow 

 cup increases in size the meshes or tubes assume an irregular shape and when the incipient 

 calicle has assumed a stellulate outline, as in the calicle farthest at left in tig. 11, most 

 of the original tubuli have vanished, a few only linger still in the centre and from the 

 lobate edge the beginning septa are direcled centripetally. In the large calicle on the 

 right, lig. 11, pl. IV, there are skeins of coenenchyma trending centripetally fi"om the 

 edges of the calicle, five or six on the right side. Between them a blank is left, a loculus, 

 altogether six, or one between each skein. It is evident through the central calicle that 

 these radiate accumulations of coenenchyma become transformed into septa, and they also 

 make it manifest to us whence the sinuosity of the septa and their lateral thorns and 

 ridges are derived, fig. 12, being in fact remnants of broken up coenenchymal tubuli. 

 Thus it is also really evident that the central reticulations in the calicles of this species 

 and so many others are actually coenenchj^mal tissue which has persisted unchanged there, 

 while the other portions Avas metamorphosed into septa. 



No law or rule common or equal for all Heliolitidas in the manner of the coenen- 

 chjanal gemmation caii therefore be established. The suggestion that the formation of 

 new calicles out of coenenchyma depends entirely on a reduction of several tubes, has 

 only in a much restricted sense foundation in the natural procedure. On the contrary, 

 as we have seen in this and in other instances, there is a formation anew and a trans- 

 formation of preexisting parts into new ones. 



Transverse sections at different depths of a polypary give, as seen in tigs. 13, 14, 

 17, 18, pl. IV, various aspects of the calicles and the coenenchyma, unlike to that of the 

 snrface. Some as tigs. 13, 17 remind of the coenenchymal gemmation and may also be 

 such. A section tig. 19 of the base of the same specimen from which the other sections 

 have been taken presents four calicles on difterent stages of development, not concordant 



