Zoarium dendritic or linear, firmly fixed to extraneous objects; zooecia tubular, not fused together to form a gelatinous mass. Subfamily B. LOPHOPINÆ. Zoarium forming a gelatinous mass in which the tubular nature of the zooecia almost disappears, capable to a limited extent of progression along a smooth surface. Both these subfamilies are represented in the Indian fauna, the Plumatellinæ by two of the three genera known to exist, and the Lophopinæ by two (or possibly three) of the four that have been described. The following key includes all the known genera, but the names of those that have not been recorded from India are enclosed in square brackets. _Key to the Genera of_ Plumatellidæ. I. Statoblasts without marginal processes. A. Zooecia cylindrical, not embedded in a gelatinous investment (Plumatellinæ). _a_. Zooecia arising directly from one another; no stolon; free statoblast oval PLUMATELLA, p. 212. _a'_. Zooecia arising singly or in groups from an adherent stolon; free statoblasts oval. STOLELLA, p. 229. B. Zooecia cylindrical, embedded in a structureless gelatinous investment. Zooecia arising from a ramifying stolon; statoblasts circular [STEPHANELLA.] C. Polypides embedded in a hyaline synoecium that conceals the cylindrical form of the zooecia (Lophopinæ). _c_. Polypides upright, their base far removed from that of the zoarium when they are expanded LOPHOPUS, p. 231. _c'_. Polypides recumbent for the greater part of their length at the base of the zoarium [AUSTRALELLA[BE].] II. Statoblasts armed (normally) with hooked processes (Lophopinæ). A. Processes confined to the extremities of the statoblast; zoaria remaining separate throughout life LOPHOPODELLA, p. 231. B. Processes entirely surrounding the statoblast; many zoaria embedded in a common gelatinous investment so as to form large compound colonies PECTINATELLA, p. 235. [Footnote BE: See Rec. Ind. Mus. v, p. 40, footnote (1910).] Subfamily A. PLUMATELLINÆ. Of the two Indian genera of this subfamily, one (_Plumatella_) is almost universally distributed, while the other (_Stolella_) has only been found in the valley of the Ganges. The third genus of the subfamily (_Stephanella_) is only known from Japan. It should be noted that zoaria of different species and genera of this subfamily are often found in close proximity to one another and to zoaria of _Fredericella_, and that the branches of the different species are sometimes entangled together in such a way that they appear, unless carefully separated, to belong to the same zoarium. Genus 1. PLUMATELLA, _Lamarck_.