PROCEEDINGS OF SECTION C. 



425 



I 



As will be seen, many of the South Australian species differ enor- 

 mously from the above type, but connecting links uniting the extremes 

 are not uncommon. 



In the present short paper I propose to describe briefly the 

 structures present in half a dozen specimens, illustrating the gradual 

 change from a conical, or almost cyUndrical, shape through those of a 

 bell-shaped habit, with spreading rims, to the extreme flabellate type, 

 which possesses nothing comparable to a calice {vide fig. 5). 



One of the simplest types of the family is illustrated in longitudinal 

 section in fig. 1, which is drawn from an etched specimen from Ajax 

 Hill (Beltana). The calicB (to use a term borrowed from the Anthozoa) 

 is about 2 cm. long, and gradually increases in width from 3 m.m to 

 8 m.m. at the distal end. Judging from the small cross section and the 



B CO 



F 



G(<2en/re^ 



H 

 K 



Fig. 1. 



Longitudinal etched section of small Cup (2 on. long), cutting 

 through Outer Wall (A and D), Inner Wall (B and G), Septa 

 (C ««<^E), Tabula (F), Initial Loculi (H), and Rhizoids (K). 



fewness of the septa, it is a young specimen. At the lower end appear 

 the lamellar attaching structures for which I suggest the name 

 rhizoid. In most specimens there is evidence of a more or less con- 

 centric growth of these rhizoid lamellae, as if the plates grew out freely 

 from the lower end of the calyx for some time and then the free ends 

 fused to form a platform {vide fig. 2). Then the lamellar growth con- 

 tinued, forming another zone of plates normal to the outer wall of the 

 calyx, and so on. Probably this lamellar structure was occupied by 

 sarcode consisting of lime-secreting cells, as in other sections (fig. 3), 

 a very luxuriant growth is evident. The earliest stage of the individual 



