NOTES ON A COLLECTION OF TERTIARY LIMEST ONES. 
Description of the borings of P. tuberosa.—Found in shell frag- 
ments which are generally more or less water-worn. Perforations 
(A type), at first slender, entering the shell at right angles to the 
shell surface or nearly so,* subsequently becoming slightly tortuous, 
and tending to give off short branches, gradually mereasing in 
width until terminated by a blunt or swollen end; colour, amber 
yellow. Other perforations in association (B type), commencing as 
an extremely fine short tube, which suddenly develops a more or 
less globular termination (? sporangium). Colour, deep reddish 
brown. Tubes and terminal swellings usually more or less filled 
with granular material, probably of the nature of spores, some of 
which are also seen scattered in the neighbourhood of the (?) sporan- 
gium. As mentioned above, no distinct septation of the vegetative 
structure visible, but occasional constrictions occur through the 
course of the tube. The borings average 13 micra in diameter, 
and 86 micra in length; sub-globose terminations averaging 18 
micra in diameter. 
Observations.—The shortness of the perforations and their charac- 
teristic clavate terminals serve to distinguish the present form 
from Dunean’s Palaeachlya perforans,t which that author found 
very widely distributed in geological time; one example described 
having occurred in a foraminifer of Ordovician age.{ 
MM. Bormet and Flahault§ have described a boring organism, 
Lithopythium, which they refer to the fungi. Their species, L. 
queketti, bears certain resemblances to the above form; it has a 
tortuous and filamentous thallus, with globular sporangia at the 
terminations and outer angles of the sinuses. It differs, however, 
in the closely interlacing habit of the thallus and the perfectly 
globular sporangia. 
With regard to Australian occurrences of Palaeachlya, Mr. R. 
Etheridge, jun., has described P. tortuosa as a parasitic species 
within a Queensland monticuliporid of Carbo-permian age.|| The 
chief characters of that species are, a flexuous tube, circular in 
section, with the terminations irregularly enlarged and with oc- 
casional swellings along the course of the tube. Another species 
instituted by Etheridge is P. torquis,§] found in the coenosteum of 
a species of Favosites from the Devonian limestone of Tamworth, 
New South Wales. This form consists of slender contorted tubes, 
filled with yellow granular matter, and having a diameter of ‘01 mm. 
It will be seen that the tube of this species is comparable in size to 
* In the case of a prismatic shell, the boring seems to be facilitated by the organism penetrat- 
ing along the principal axial line or prismatic direction, for easy solution of its base of attack 
may constitute an important factor in its growth. 
+ Quart. Journ. Geol. Soc., vol. xxxii., 1876, p. 205, pl. xvi. 
t Loc. cit., pl. xvi., fig. 5. 
J § ‘Sur les Algues Perforantes,” Bull. Soc. Bot., France, vol. xxxvi., 1889, p. elxxii., pl. zi, 
gs. 5, 6. not & we 
Rec. Geol. Surv. N.S.W., vol. ii., pt. 3, 1891, p. 95, pl. vii., fig. 1. a 
Rec. Aust. Mus., vol. iii., No. 5, 1899, p. 121, pl. xxiii., fig. 5. 
7965.—D { 41] 
