1(J8 
JOAX ^I. CROCKFOm). 
0-3 mm.; about thiry-seven apertures occur in 10 imn. The fenestrules 
are from 0-29 to 0-52 nmi. in length and from 0-17 to 0-4 mm. in width; 
the width of the dissejiiments is from 0-1 to 0-29 mm., but is generally 
less than 0-2 mm., and the length of one fenestrule and one dissepiment 
is from 0-49 to 0-65 mm. (average 0-57 mm.). The dissepiments, when' 
they are well-preserved, may show two or more fine transverse ridges, and 
the whole of the celluliferous surface is covered by very tine tubercles. On 
the reverse surface both branches and dissepiments are evenly rounded, and 
the dissepiments may be as thick as the branches; the outermost layer is 
finely granular, and the backs of the branches may be ornamented by fine 
nodes, thoug’h these are not always developed over the whole of the reverse 
surface, and are easily worn away. The inner layers of the reverse surface 
show fine longitudinal striae. Bifurcation occurs usually at distant intervals, 
though it may be frecjuent; increase to the three rows of zooecia occiu’s im- 
mediatelv before branehing:. 
Remarks: Fenesfr€lli}ia horologia was described by Bretnall from the 
Gascoyne River District; it occurs as low in the Permo-Carboniferous as 
the Callytharra Stage; and occurs also in Queensland (Consuelo Ck., two miles 
above Cattle Creek, S]'»ringsure District; Reid, 1930, p. 157, locality 9). 
It appears to be the same as Fenesirellina parvinscula (Bassler), which occurs 
in Timor in both the Bitaoeni and Basleo beds. F. parvinscula has also been 
recorded from the Permian of Vancouver Island. 
Fenestrellina disjecta sp. nov. 
Plate 1, Fig. 2; Text-figure 1 F. 
Holotvpe: Specimen 2793a, University of Western Australia Collection. 
(Coll. IT. W. B. Talbot.) 
Horizon and locality: Xooncanbah Series; fiV'g Xorth of ]Mt. 
Anderson. 
Fenestrellina with four to five zooecia to a fenestrule ; slight carina; 
verg high nodeSj one occurring in the length of each fenestrule. and usually 
placed opposite the junction of a branch and. a dissepiment. 
The form of the colony is not shown ; there are 12 branches horizontally, 
and 10 fenestrules vertically, in 10 mm. The branches are straight, from 
0-33 to 0-4 mm. in width, and shoAV a slight median carina, bounded by a 
depression on each side. Very high nodes, Avith their bases elongated parallel 
to the length of the branches, occur at inteiwals of from 0-98 to 1-17 mm., 
and are generally jdaced opposite the junction of a dissepiment Avith a 
branch; in well preserved specimens the height of these nodes is up to 
0-25 mm., but they usually appear very much smaller. The apertures are 
circular, 0 08 mm. in diameter, and are surrounded by distinct peristomes. 
Four, less often fiA'e, apertures occur in the length of one fenestrule and one 
dissepiment; the distance betAveen the centres of successive apertures is from 
0-21 to 0-28 mm. (average 0*25 mm.') and about forty apertoes occur in 
10 mm. The fenestrules are oA'al, from 0-7 to 0-94 mm. in length, and from 
0-29 to 0-54 mm. in Avidth; the dissepiments arc from 0-14 to 0-24 mm. in 
AAudth, and the length of one fenestride and one dissepiment is from 0-89 
to 1-lfi mm. On the celhdiferous suiTace the dissepiments are slightly 
rounded and shoAv four or five fine ti*ansA*erse ridges and grooA'es. On the 
reverse surface both branches and dissepiments shoAV numerous fine longi- 
tudinal striations AAliere they are slightly weathered. The dissepiments are 
distinctly thinner than the branches. At their junction Avith the dissepiments 
