CELLULARINE AND OTHER POLYZOA. 349 
,parts of J and K. The joints are on the distal side of C and D, and traverse 
the proximal ends of GK and FJ without passing through an opesia. 
Rootlets given off on the distal side of the joint. Zooecia elongated, the 
opesia relatively short. Basal avicularia, approaching a vibraculoid form, 
■typically present, and then usually confined to the neighbourhood of the 
axils ; the rootlets given off by them or from other parts closely applied to 
the margins of the branches and strengthening the axils. Scutum, frontal 
and marginal avicularia present or absent. Ovicells typically large, and with 
a frontal fenestra. Zoarium biserial. 
I propose this genus primarily for several deep-water species represented 
in the ' Siboga ' Collection, all of them supported by an elongated stalk 
composed of parallel rootlets, which diverge at the base to form an anchoring 
■tuft — a type of growth frequently found in Cheilostomes from deep water. 
I select as the genotype JS'. rostratus, of which I give a preliminary diagnosis; 
this species representing the genus in what I consider the full expression of 
its characters., some of which are lost in other species. The features which I 
regard as specially characteristic are : (1) the lilode of bifurcation, the joints 
being at a considerable distance from the axil (a convenient way of 
recognizing members of the genus), and the position of the joints, wliich are 
completely on the distal side of and D ; (2) the occurrence of basal 
heterozooecia, commonly confined to the bifurcations. Certain species do not 
possess these structures, but their affinity is indicated by the mode of 
branching. 
JYotoplites appears to be allied to Amastigia, as shown by the occurrence of 
basal avicularia ; but it differs from that genus in being biserial and jointed, 
in the longer zooecia, and in having tlie basal avicularia confined, as a rule, to 
the bifurcations. It differs from Menipea in the fact that the joint does not 
traverse the opesia of the inner zooecium at a bifurcation. It will be observed 
that the genus, as here understood, occurs from the Arctic to the Antarctic 
Oceans, but that a connecting-link is afforded by the ' Siboga ' species, from 
the neighbourhood of the equator. 
1. NOTOPLITES ROSTKATUS, n. Sp. 
Zoarium reaching a length of 55 mm., attached by a proximal tuft of 
rootlets which separate from a main stem, about 20 mm. long, composed of 
parallel rootlets. Zooecia long and narrow, their outer outline concave ; the 
opesia, which occupies less than half the frontal length, oval, much reduced 
proximally by a broad, crescentic cryptocyst. Distal spines 2 external, 
1 median, 1 internal, with another arising from the basal surface. Scutum 
jointed at the base, the lamina lobed, its distal portion the smaller and 
generally acutely pointed and narrow. Frontal avicularium, in ordinary 
zooecia, variable in size, elevated, at some distance from the opesia, on the 
inner side of the cryptocyst, reclining against the opesia of the preceding 
