93 
The form has been closely compared with examples of 
Magellania flavescens of the same size, and is immediately 
distinguished from them by its general shape, and especially 
by the very differently-shaped beak, and by the complete 
absence of ribs, which are already quite plain in really 
small examples of Jf. flavescens. Again, in the formation 
of the brachial apparatus distinct differences present them- 
selves. By the general form, one might be reminded of 
young examples of M/. lenticularis (the illustration of David- 
son, Recent Brachiopoda, pl. ix., figs. 2 to 13), although this 
is not yet known from the Australian coast. But against 
this likeness are the much more strongly hook-shaped curved 
beak in the last-named form, the very small diameter of the 
inner orifices of the pores (scarcely 10 »), and the quite dis- 
tinct pattern on the valves. Also, the brachial apparatus 
of the young figured example of Davidson is quite different. 
So ib remains only to regard the examples before us as repre- 
sentatives of an independent new species. 
= E, acl las 
stralis, n. sp., Blochmann. PI. xxvii., a 
figs 10 to 12. 
Shell as long as broad. Colour dirty-yellow. 
Length and breadth are equal, thickness amounts to 
about one-half of this. Because the dorsal valve is bounded 
behind by a straight hinge-line, it approaches a semicircle in 
outline. The complete outline is altered by the triangular 
beak. The end of the beak is flatly rounded. Its edges are 
sharp. Between them and the hinge-line is a flat area. 
Deltidial plates seem wanting. The hole of the beak is large, 
bounded towards the front to a considerable extent by the 
hinge-margin of the dorsal valve. 
Each valve bears a moderately conspicuous median 
sinus, and on each side of this three ribs, increasing rapidly 
in width towards the periphery. These project at the edge 
as rounded teeth, so that if the posterior corner is included, 
four rounded teeth are found at the edge, on each side of the 
notch corresponding to the median sinus. These are not 
always quite distinct, so that the edge often appears only 
flatly undulating. Also, variations occur between the right 
and the left. The growth striz in both valves are quite dis- 
tinct. Both valves are about equally deep. There are about 
320 pores to the square millimetre; inner diameter of these, 
about 10 »,; outer diameter, about 15-20 »; frequently oval, 
20 p by 10 p. 
The edge of the pedicle hole forms a conspicuous collar. 
In the ventral valve is found an indistinct median septum 
