76 
RECORDS OF THE AUSTRALIAN MUSEUM. 
Each thread-like lyrula of the sculpture is separated from its 
neighbour by several times its own thickness, the obliquity of the 
lyrulse on the upper part of each whorl being changed on the 
straight- walled portion to a perfectly vertical direction. The 
upper part of the inner lip, although not forming a callosity, is 
revolute, slightly projecting over the umbilicus. The aperture 
was long oval, angled on the outer lip by the principal keel of the 
body whorl. 
Loc. and Horizon . — Gordon River, West Tasmania. Gordon 
River Limestone, Lower Silurian. 
TROCHONEMA? NODOSA, Sp. 710V. 
PI. xv., Figs. 9, 10. 
Worthenia , sp. nov., Ratte, Proc. Linn. Soc. N.S. Wales, x., 1885, 
pt. 1, p. 80, t. 9, f. 1 and 2. 
Sp. char. — Shell turbinate, but not depressed ; whorls more 
than four (four in part only preserved), the body whorl apparently 
not free, each whorl horizontal or nearly so on its upper portion 
around the suture, vertical or straight- walled in the lower ; all, 
except the body whorl, bear two keels, the latter three, the upper- 
most keel in each case demarcating the two portions of the whorls, 
and carring a number of blunt nodes, or tubercles, which on the 
body whorl become of a variciform nature, and more pronounced 
with the growth of the whorl ; the second keel is midway between 
that just mentioned and the suture, and with the third on the 
body whorl is nodose also. Mouth generally oval, vertically elon- 
gated ; outer lip quadrangular ; inner lip and minute sculpture 
not preserved ; umbilicus deep and apparently open. 
Obs. —Had not Mr. Ratte figured this shell, and referred it to 
Worthenia (with which it has no connection), without a specific 
name, I should not have noticed it in consequence of its poor state 
of preservation. I am even doubtful of its proper generic resting- 
place from the same cause, but Trochonema , so far as L can judge, 
seems to be the most appropriate genus. At the same time it departs 
from the majority of species referred to the latter by the nodose 
nature of the encircling keels. There is one species of this genus, 
however, similarly ornamented — T . yandella7ia> Hall & Whitfield,* 
from the North American Corniferous Limestone, but otherwise 
distinct from T. ? nodosa. It may even be related to our old 
friend Bucciiiwn breve, Sby., of the British Devonian rocks, and 
which W hid borne has of late refer red f to the recent genus Liotia , 
Gray, without, however, in my opinion, sufficient reason. 
* 24th Ann. Rep. N. York State Cab., 1872, p. 194; 27th ibid., 1875, t. 
13, f. 3; Nettelroth, Kentucky Fossil Shells, 1889, t. 20, f. 3. 
f Mon. Dev. Fauna S. England, 1892, pt. 4, p. 271. 
