55 
of Edinburgh , Session 1880 - 81 . 
the left side and posterior end. Colour, dull gamboge yellow, with 
a little reddish-brown at the posterior end and the left side. 
Length, 8 cm. ; breadth, 4 cm. 
Test leathery, rather thin except at the area of attachment and 
on the siphons. Inner surface white, with a few yellowish-brown 
patches. 
Mantle strongly muscular on the right side and the dorsal part of 
left, membranous on the ventral part ; musculature strong and 
regular. 
The muscular band at the base of the branchial siphon, and just 
above the tentacle ring, bears four large bluntly conical processes 
projecting into the lumen of the tube. 
Branchial sac with six folds on each side. The alternate trans- 
verse vessels larger than the intermediate ones. Internal longi- 
tudinal bars numerous, eight or nine on the folds and about twelve 
on the interspace, which has six wide and six narrow rows of 
meshes. The largest meshes have each six to eight stigmata. 
Dorsal lamina plain. 
Tentacles compound, twenty in number, large and small alter- 
nately. 
Olfactory tubercle broadly cordate, both horns rolled inwards. 
One specimen from Station 188 (between Australia and New 
Guinea), 28 fathoms. 
This species externally is not unlike Microcosmus polymorphus , 
Heller, but differs from it notably in having only six folds in its 
branchial sac, in the condition of the test, and in having projections 
n the branchial siphon above the circlet of tentacles. 
Microcosmus polymorphous, Heller.* 
One large specimen from Station 162 (Bass’ Strait), 38 to 40 
fathoms. 
Microcosmus propinquus, n. sp. 
External appearance . — Shape oblong-ovate, or almost triangular, 
flattened laterally ; anterior end narrow, dorsal and ventral edges 
* Heller, loc. cit. p. 6. 
