OCCURRENCE OF SPIRANGIUM IN THE HAWKESBURY SERIES, 205 



NOTE on the OCCURRENCE of the GENUS SPIRAN- 

 GIUM in the HAWKESBURY SERIES OF 

 NEW SOUTH WALES. 



By W. S. Dun. 



With Plate XIV. 



[Read before the Royal Society of N. 8. Wales, December 4, 1912.1 



Through the kindness of Mr. W. Gelme, I have had the 

 opportunity of examining four imperfect specimens of 

 Spirangium from the brickpits at Brookvale, near Manly. 



The specimens occur as impressions in a blue-gray shale 

 associated with Phyllotheca, Alethopteris sp., Thinnfeldia, 

 and fish — Cleithrolepis, Semionotus, Dictyopyge, and 

 Pristisomus ? 



The most perfect specimen, that figured on Plate XIV, 

 has a length, as preserved, of 19 cm., but the stalk-like 

 appendages are imperfect — the inflated vesicle (?) is 10 cm. 

 long, and the spindle-shaped body is traversed by two 

 opposed series of helicidal ridges, each nine in number, 

 dividing the surface into compartments 7 by 10 mm., 

 broader than long on the main mass, though at the extremi- 

 ties the tetragonal compartments are naturally more 

 elongated. 



These peculiar fossils have been found at various horizons 

 from Carboniferous to Lower Mesozoic in Europe and 

 America, and have been described under several generic 

 names — Palasozyris, Palaeobromelia, Fayolia — a much 

 larger form from the Permian of France which may have a 

 similar origin. 



The forms are generally classed now under the name of 

 Spirangium and though various interpretations have been 



