1 
160 THE VOYAGE OF H.M.S. CHALLENGEE. 
long. 70° 12' E. ; in from 20 to 25 fathoms ; sea-bottom, volcanic mud ; and 
cigain on January 13, 1874, in 25 to 30 fathoms. A single specimen (about one- 
third grown) occurs from Balfour Bay (Station 149c), January 19, 1874; depth, 
60 fathoms; and a similar example, labelled “ Eoyal Sound,” was dredged on the 
following day. 
The two largest specimens were dredged at Station 151, February 7, 1874 (off Heard 
Island) ; lat. 52° 59' S., long. 73° 33' E. ; depth, 75 fathoms ; surface temperature, 36°'2 ; 
sea-bottom, volcanic mud. 
The large specimens, which greatly exceed Professor Grube’s, measure 220 mm., 
with a diameter of about 20 mm. anteriorly. 
The outline of the body agrees with the typical forms, and the general colour of 
the larger specimens is iridescent, dull brownish in front, paler posteriorly, or dull 
iridescent, violet anteriorly, and somewhat paler posteriorly. The smaller examples are 
pale. 
The head is somewhat shield-shaped with the point posterior, and a small pit exists 
on each side, a little in front of the latter. The tentacles and subtentacles are short and 
conical. The exserted proboscis (PI. XXVI. fig. 4) forms a short thick cylinder with a 
distal division terminated by a prominent series of double papillge, ten on each side. The 
central hiatus superiorly is occupied by a single shorter papilla, while the ventral hiatus 
has a short bilaterally divided papilla, the other ten being split radially. Fissures run 
down between each of the double papillse internally, and the somewhat dense mucous 
membrane is cut into various areolas, which in a modified form may foreshadow the mouth 
of the Lamprey. Externally the furrows pass to the base of the distal division. The 
succeeding and larger region is ovo-cylindrical, and its surface is furnished with a 
number of prominent papillae, which, with the exception of the median parts dorsally 
and ventrally, are rather irregularly arranged distally. By and by the papillae diminish 
in size, and towards the base group themselves into fourteen rows, which proximally are 
bifid. The two horny conical jaws are similar to those in Nephtliys cceca, and are largely 
developed. 
The superior lamella of the foot (PI. XXVII. figs. 1, 4) is broad as well as 
elevated, and is rounded all along the free margin. The next lamella springs from the 
base of the branchia, and widens so as to assume a broadly ovate shape with a 
pointed apex. The inferior lamella is ovato-lanceolate, and in the larger examples 
is much developed. In young specimens all the lamellae are larger and as a rule 
more perfect, and in a variety from Eoyal Sound (PI. XXX. fig. 8) these are unusually 
large. The cirriform branchial process is coiled inward, and in several is the seat 
of a minute parasitic Nematoid, which has a blunt snout and a pointed tail. The 
latter shows a series of about nine regular loop-like markings above the anus. The 
