320 THE PROCEEDINGS OF THE LINNEAN SOCIETY 



mediate sub-division called Faviacecs, where the corallites 

 multiply by successive fissiparity, but are soon individualized and 

 are grouped without order in a massive coral. 



Among the simple Lithophylliace^, (Mussaceoe) we have one 

 which Prof. Duncan has referred to his genus Antillia. It is a 

 discoid form whereas in the definition of the genus, {Quart. Jour. 

 Geol. Soc Vol. 20, p. 28), it is said the coral is short, turbinate, 

 and pedicellate. I subjoin the Professor's definition of the 

 species which is a fossil, but as I have met another species it may 

 be desirable to separate the discoid forms into a distinct genus. 



Antillia lens, Duncan. 



Coral is the shape of a Cyclolite (Fungidce) ; the base is 

 circular in outline, nearly flat, the concavity being very slight ; 

 the epitheca is pellicular and faint ; the costse are seen as radi- 

 ating flat elevations, those corresponding to the smallest septa 

 being the smallest ; the margin of the base presents slightly 

 exsert equal processes, which are the septa ; the upper surface 

 of the coral is convex and nearly hemispherical, the depression 

 for a small essential columella, formed by processes from the 

 base and septal ends being slight ; the septa are in six systems 

 of four cycles ; the primary and secondary septa are equal, and 

 the tertiary are nearly as large ; those of the fourth and fifth 

 orders are somewhat less ; all are very convex superiorly, and 

 less so and nearly straight externally ; the laminae are thin, and 

 are very strongly marked by sharp ridges, which radiating from 

 the basal part of each septum are more or less parallel, and give 

 at the free margin a laterally dentate appearance ; this appear- 

 ance is less marked in the smaller septa ; there is often a pali- 

 form process on the larger septa, near the columella, and the ter- 

 minations of the ridges give the dentate character to the free 

 margin of the septa; the endotheca is scanty, stout, and inclined. 

 Breadth -^ inch, height -f^ inch. 



Locality Hamilton, Victoria, S. Australia. 



