REPORT ON THE HYDROIDA. 21 
Zamboanga—which in the form of the hydrothece and in the general habit of the colony 
closely approaches Plumularia dolichotheca. It differs from it, however, in every internode 
of the hydrothecal pinne carrying only one hydrotheca, and in the opposite instead of 
alternate disposition of these pinne. 
Plumularia dolichotheca was dredged off Zamboanga, Philippines, 30th January 1875, 
from a depth of 10 fathoms. 
Plumularia insignis, n. sp. (Pl. IL). 
Trophosome.—Colony attaining a height of about eighteen inches, main stem fascicled, 
sending off in all directions simple jointed branches, along whose entire length the hydro- 
thecal pinnze, about two-tenths of an inch in length, are alternately disposed. Hydro- 
thecee deep conical, adnate by their entire height to the supporting mternodes, which are 
separated from one another by an intervening much shorter internode, destitute of hydro- 
theca; mesial nematophores situated one on the hydrothecal internode at the proximal side 
of the hydrotheca, and one on each of the intervening internodes. 
Gonosome.—Gonangia situated on the hydrocladia-bearing branches, each at the base 
of a hydrocladium. 
This very beautiful species is rendered especially striking by its large size and its 
plume-like ramification. The gonangia present in the specimen seem to be young, and to 
have scarcely yet attained their ultimate form. Several specimens of a little isopodous 
crustacean continued to adhere to the stem, and are represented in the drawing. 
Station 145, December 27, 1873, lat. 46° 40’ S., long. 37° 50’ E.; depth, 310 and 
150 fathoms. 
Plumularia abietina, un. sp. (Pl. IIL). 
Trophosome.—Colony attaining a height of about nine inches, main stem fascicled for 
some distance from its root, and sending off scattered, usually simple jointed branches, 
which carry alternate hydrothecal pinnz, rather less than two-tenths of an inch in 
length, and commencing from a point at some distance from the origin of the branch. 
Hydrothecs deep conical, adnate by their entire height to the supporting internodes, which 
are separated from one another by an intervening much shorter internode, destitute of 
hydrotheea; a single mesial nematophore, borne by the hydrothecal internode at the proxi- 
mal side of the hydrotheca, and another on each of the intervening internodes. 
Gonosome.—Gonangia ovate, borne by the hydrocladia-bearing branches, each close to 
the origin of a hydrocladium. 
The Hydroid here described comes very near to Plumularia insignis ; indeed, so nearly 
related are the two forms, that we should almost be justified in regarding the difference 
between them as merely varietal. 
