PYCNOGONIDA. 35 
CH&TONYMPHON AUSTRALE, va’. AUSTRINORUM, 
(Plate IV., fig. 4; Plate X., fig. 15.) 
Although no specimens of Chzxtonymphon australe were taken by the ‘ Discovery,’ 
yet a large number of individuals of a closely allied species were taken in Winter 
Quarters, chiefly at the beginning of our stay there, before the ship was frozen in, and 
while dredging was still possible within the 20-fathom line. 
At first sight these specimens seem to be a distinct species; they are half as large 
again or more, and their setose covering is finer. The intervals between the lateral 
processes are much greater, and this is the only character of importance that separates 
them. Another feature of doubtful value lies in the fact that the tarsus and propodus 
together are distinctly shorter than the femur. In C. australe these two joints are as 
long as the femur, or very little shorter, but the slight variation that occurs prevents 
the acceptance of this fact as a reliable specific character. 
The setose covering has already been alluded to as finer; it is so, but subject to 
considerable variation both as to quality and quantity. In average specimens there are 
large spinous setz on the tibiz, especially on the second. These are, for the most 
part, arranged in a line but not very distinctly. Two dorsal rows, and a lateral row 
each side can be distinguished, these are most prominent on the second tibia. There 
may also be a mid-ventral row of very small spinous sete, rather closely set. Both 
in C. australe and the specimens from Winter Quarters the ventral setz of the 
femora and the two tibiz are much less conspicuous than elsewhere. In many indi- 
viduals there is a conspicuous mid-ventral row of sete: on the tarsus; these are closely 
set and about as long as the diameter of the joint. 
Two specimens were taken in 100fm. off Coulman Island ; of these one is com- 
paratively small. The Ocular tubercle is rather more conspicuously flattened and very 
slightly constricted below the eyes. The sete are as in the Winter Quarters 
specimens, but without the spinous rows which, as before noted, are not always obvious. 
Two other specimens were taken off the Barrier in 300fm. Lat. 78° 25’ 40” 8, 
long. 185° 39’ 6” E. These are both males, one with young. In these the Ocular 
tubercle is flattened, as in the Coulman Island specimens, and the terminal claw of the 
lee is rather longer and more slender. The setose covering of the legs is very much 
finer, but its arrangement is exactly the same. 
It is quite impossible to find a distinct character by which these specimens can be 
separated from C. australe, therefore I feel compelled to regard them as a variety only, 
and a more southern form of that species. Some comparative measurements are given 
below. 
C. australe. C. australe, var. austrinorum. 
Wii): Coulman, Barrier. 
Length of entire body . : : . 8mm. 11 Ye 2 12 
Length of body . ; . . . 6mm. 8 55 95 Sa 
Length of trunk, to insertion of abdomen 4°5mm. 6 4 7 7 
