Tertiary.) PALAONTOLOGY OF VICTORIA. [Protozoa and Zoophyta. 
Pirate XLVIII., Fie. 1. 
TETHYA NEWBERYI (McCoy). 
: [Genus TETHYA (Lam.). (Sub-kingd. Radiata. Class Protozoa. Order Rhizopoda. Fam. 
pongide.) 
Gen. Char.—Sponge tuberous, compact, invested with a distinct rind or skin, interior 
sarcoid with numerous very long slender, silicious spicula, collected into bundles and radiating 
from a more compact nucleus to the circumference. Marine. ] 
Description.—Forming irregularly lobed masses from 1 to 2 inches in diameter, 
composed of long setaceous spicula, radiating from a point, and grouped in bundles; 
each spicule hollow, nearly smooth, straight, or nearly so, circular in section and 
tapering to a point at each end. About eighteen spicules in the transverse space of 
1 line ; some apparently about 1 inch long. 
The first specimen obtained of this object was sent to Mr. Cosmo 
Newbery for analysis as a mineral species, but he, perceiving that 
the fine fibres of which the mass was composed were pure silex, 
forwarded the specimen to me as probably an organic fossil. I 
have great pleasure in dedicating the species to my excellent 
colleague, whose chemical researches have been so beneficial not 
only to the geological survey but to the colony at large. 
The fine hairlike or “asbestiform,” hollow, silicious spicules 
exactly accord with those of sponges of the recent genus, Tethya, in 
size, shape, structure, and chemical constitution, in their radiated 
arrangement, and tendency to associate in imperfect bundles ; like 
them, also, the pointed lower and upper ends do not extend usually 
the whole way from the point of radiation (which probably agrees 
nearly with the point of attachment), but they arise and terminate 
occasionally at various intermediate points. I have not seen any 
triradiate terminations to any of the spicules such as occasionally 
occur with the simple forms in the recent Tethya, but they are so 
brittle that such may yet well be found. The general form of our 
fossil is not so regularly spheroidal as in the living European 
Tethya cranium, but is rather more lobed and irregularly flattened 
in parts as in the Tethya penicilliformis of Gray (or Halichondia 
mammillaris of Johnston), but the “ asbestiform” spicules of both 
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