212 
one specimen had besides a pupal stage (C) attached to the margin 
of the right gill-cover (like the single case previously found and 
mentioned on p. 16 of my paper); another carried a Cyclops-stage 
(A) in front of the right ventral fin, and on the bottom of the 
tube was found one more of the same stage (A), dropped off from 
its host. 
The adult female Sarcotretes of the Scopelus with the Cyclops- 
stage is coated with a beautiful colony of JZchthyocodium, while the 
remaining 8 are without any Hydroid. The basal membrane of 
the new Ichthyocodium encloses completely the external part of the 
Sarcotretes; it is thicker than in any specimen hitherto found, and 
its anastomosing tubes are numerous and often provided with 
blindly ending branchlets. A large number of the polypes are 
long (ca. 2 mm.) and slender; many or most of them carry medusæ- 
buds basally. The largest medusæ-buds are somewhat more advanced 
than those previously observed, not only larger (ca. 0,8 mm. in 
length, 0,224 mm. broad) but more medusiform, and attached by 
means of a longer and slender stalk; indications of a pair of 
additional marginal tentacles are quite distinct; thus my assumption 
(1.c. p. 23) that the medusæ, when liberated, might possess 4 
marginal tentacles has been confirmed. The manubrium has still 
no mouth-opening, nor have I been able to observe genital cells. 
Furthermore, among some Museum specimens of Scop. glacialis, 
captured several years ago at the coasts of Greenland, a single one, 
37 mm. in length, labelled: Sukkertoppen, Miller 5/6 1890, has been 
found infested with an adult Sarcotretes without Hydroid. Probably 
it has been brought by some Eskimo to the Colonial Director R. 
Miller, who in 1889 sent a valuable collection of fishes to 
the Museum. The colony Sukkertoppen is situated at ca. 65? 25” 
Lat. N., 52? 45'. Long. W. 
The total number of the Sarcotretes in its final, inserted 
shape examined by me now amounts to 32 instead of 22, that 
of metamorphosis stages to 37. Of the 10 new adult females 
5 protruded dorsally, all in front of the dorsal fin, 5 ventrally. 
