THE BRACHIOPODA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 377 
south-west of the South Shetlands, the possibility of the large size being influenced by 
shallowness in depth cannot be determined. 
The specimens obtained by this Expedition are very oval in shape, like the Scotia 
Bay examples, and, as in the latter, they also possess a curious labiate prolongation of 
the foramen over the dorsal umbo (see fig. 1, and OEHLERT, 1908, pl. i.), which does 
not appear to be present in the South Georgia examples or in normal specimens of 
L. uva from Burdwood Bank and neighbouring stations. 
The shells, too, possess a greater vertical diameter owing to the rotundity of their 
valves, and the angular appearance of the lateral margins, present in L. wva, is absent 
(compare BLOCHMANN, 1912, pl. i.). 
To the above-mentioned differences must also be added an important variation in 
the composition of the shell-mosaic and the perforations of the test, based upon a study 
of the Scotia Bay examples. 
Here the number of pores per square millimetre in specimens Nos. 2 and 3 is 96 
to 128. These examples are, unfortunately, too opaque for a detailed study of the 
mosaic. 
An examination of different portions of both valves of the young example No. 4, 
shows a range from 88 to 128 pores per square millimetre. The shell-mosaic is here 
clearly visible and consists almost throughout of a well-developed imbricating structure, 
with scarcely any trace of the irregular character exhibited in young examples of 
L. wea (2°75 and 5 mm. in length) from the Burdwood Bank material. The number 
of pores in the latter specimens ranges from 200 to 256 per square millimetre. 
It may be of some interest here to call attention to a number of fossil forms of 
Terebratulidz which have recently been described from the immediate neighbourhood 
of Graham Land, to the south-west of the South Orkneys. 
In the report on the Antarctic fossil Brachiopoda collected by the Swedish South 
Polar Expedition, Buckman (1910) describes, under the generic name of Terebratula, 
several very interesting forms, which appear to me to have some bearing on the recent 
species now inhabiting the neighbouring seas. 
Amongst the coarsely punctate series three forms are described, two of which are 
referred to previously described fossil species; the other, owing to its fragmentary 
character, is not specifically determined. 
One of these forms is referred by Buckman to Terebratula bulbosa, Tate (a species 
met with in Australian Tertiary strata), with certain slight modifications in the 
description to suit the Antarctic specimens. 
Without a comparative study of the Australian and Antarctic forms it is impossible 
to say if this identification is correct or not, but it appears to me possible that the two 
forms are in no way related to each other. 
Buckman’s figure* (pl. i. fig. 7), which is a restoration, and his revised 
description present, in my opinion, striking resemblances, so far as external appear- 
* The labiation of the foramen has been overlooked by the artist. 
