MARINE ZOOLOGY in common. The writer has observed nearly the same phenomenon, and in a specimen before him the union of two ooecia is seen in different phases of com- pleteness. The cause is evidently over- crowding, the zocEcia in which it occurs being extremely narrow. Associated with the last species ; not uncommon. Hast- ings. 67. Smittia cheiloitoma^ Manzoni. Occurring as light red patches upon old shells and stones. Zooecia coffin-shaped, rather pointed below ; front wall perfor- ated ; aperture raised, sub-circular, but with a large sinus in the lower margin ; within is seen a flat-topped process. As already stated elsewhere, the immature zooecia of this species resemble nearly the zooecia of Lepralia pertuia. Common from deep water. Hastings. 68. Smittia trispinoia, Johnston. Forming large bufF-coloured patches upon old shells, stones, etc. Aperture raised, sharp, with a sinus in the lower lip, and in some cases four spines above. Below the aperture on one side, and pointing towards it, is an avicularium ; and around the margin of the zocecium are a series of pits or per- forations. From moderate to deep water ; very common. Hastings. 69. Phylactella lahrosa, Busk. Upon shells. Zooecia ovate, short, per- forated, and arranged in single divergent lines. The aperture is round, raised and expanded, and shows a small denticle with- in. From deep water ; somewhat rare. Hastings. 70. Phylactella collaris, Norman. Colonies more compact than in the last species. The front wall is plain, and there is no denticle upon the lower lip of the aperture, which is sometimes slightly pointed. Upon old shells. From moderate to deep water ; not very common. Hast- ings. 71. Mucronella peachii, Johnston. Encrusting dead shells, stones, etc. Zooecia ovate to lozenge-shaped ; aperture round, with six spines around the upper margin ; upon the lower lip, within, is a double-pointed denticle, and upon the outer lip a small conical tooth. The area below the aperture is rather swollen. Common from moderate to deep water. Hastings. 72. Mucronella ventricosa, Hassall. This species much resembles the last, but comparison, by the aid of a handglass only, will show colonies to be of coarser grain, or composed of larger zooecia. These are ventricose, the aperture has four instead of two spines, and there is a tongue-like process projecting from immediately below the lower lip. Common upon shells from deep water. Hastings. 73. Mucronella variolosa, Johnston. Colonies encrusting dead shells. When in good condition they have a strong violet lustre. The zooecia are coffin-shaped and pitted around the margin ; aperture, round to subquadrate, with two long spines upon the upper rim, and a small process or tooth upon the lower one ; behind which is seen a flat-topped process. Common from moderate to deep water. Hastings. 74. Mucronella coccinea. A very handsome species of a violet lustre. The zooecia are rather short, wide, and with marbled markings. The aperture in marginal zooecia is circular, with six spines upon the upper rim and a pointed process upon the lower lip. Upon both the right and left side of the aperture is a formidable-looking avicularium, one of them sometimes being very large. Not un- common upon rock and other objects from deep water. Hastings. Mucronella coccinea var. mammilatay answering exactly to Hincks' description, occurs also at Hastings. Upon shell of Pectunculus glycymeris. 7 5 . Palmicellaria sienei, Ellis and Solander.* Hastings. CELLEPORIDiS 76. Cellepora pumicosa, Linnxus. This species by successive layers of zooecia forms rounded masses of a few inches in diameter, upon scallop and other shells. The zooecia are oval, upright, with circular aperture, and a long, pointed ros- trum arising from beneath it, and carrying a small avicularium. Common from deep water. Hastings. 77. Cellepora avicularis, Hincks.* Hastings. 78. Cellepora costazii, Audouin.* Hastings. Cellepora costazii vat. tubulosa, Hincks.* Hastings. 91