place the tube is generally constricted. In G. problematical, on the con¬ 
trary, the tube appears to be of indefinite length, and contortedly coiled 
upon itself. The diameter of the tube in both species is about the same. 
In G. problematica the tube is loosely wound, whilst in the present species 
it is densely packed together. G. conjerta also occurs in a slide of Wenlock 
limestone from Dudley, England, prepared by the writer several years ago. 
Locality and Horizon .—Tyers River, Gippsland, and Cave Hill, Lily- 
dale. Silurian (Yeringian). Also in the Silurian (Wenlockian) of Dudley, 
England. 
Girvanella cf incrustans, Wethered (non Bornemann sp.) 
Plate V., figs, n, 12. 
Girvanella incrustans , Wethered, 1890, Quart. Journ. Geol. Soc., Vol. 
XLVI., p. 280, PI. XI., figs. 1 a, b. 
Observations. —Certain of the Girvanella pellets in the Tyers River 
limestone have very tortuous tubes, closely packed, the tubes measuring 
.014 mm. in diameter. This 'form closely approaches the above-named 
species described by Wethered from the Carboniferous Limestone of 
Clifton, England, both as to the size of the tubules and their habit of 
growth. 
Locality and Horizon. —Tyers River, Gippsland. Silurian (Yeringian). 
Girvanella (?) pisolitica, Wethered. 
Plate V., fig. 10. 
Girvanella pisolitica , Wethered, 1889, Geol. Mag., Dec. III., Vol. 
"VI., p. 200, PL VI., fig. 10. 
Observations. —A form of Girvanella also occurs rather frequently in 
the Tyers River Limestone, which resembles in some respects the above 
species described and figured by Mr. Wethered. It is an encrusting form, 
found adherent to organic fragments, such as joints of crinoids. The 
tubes are much larger in diameter than they are in the other forms of 
Girvanella , and the earlier part of the (?) thallus is composed of sphae- 
roidal or ovoid segments, having a comparatively thick, translucent cell- 
wall, apparently non-calcified, and usually of a pale brown colour (PI. 
IX., fig. 10). This segmented series is often seen to pass into the 
greatly extended tube typical of the Girvanella structure forming the bulk 
of the pellet, by more and more elongated cells, divided by transverse or 
oblique partitions. The several segments bear some resemblance to the 
il SchLauche mit Sporangien ” in Rothpletz’s SpJioerocodium 1 ; and 
Wethered also figures a nodule of Girvanella (G. pisolitica )' 2 from the 
Inferior Oolite of Cheltenham, England, which shows a linear series of 
small sub-spherical segments, such as are found in the Gippsland 
forms. The diameter of the spherical or pyriform segments in our speci¬ 
mens averages .07 mm. 
Locality and Horizon. —Tyers River, Gippsland. Silurian (Yeringian). 
1 Zeitschrift Deutsch. Geol. Gesellsch., vol. xliii., 1891, pi. xvi., figs. 4, 5. 
- Loc. supra cit ., fig. 10. 
