Page:VCH Sussex 1.djvu/136

 A HISTORY OF SUSSEX 55. ScMzotheca fiisa, Busk. ZocEcia ovate, small, short ; aperture elevated, with six spines and a narrow sinus in the lower lip ; ocecium sub-cres- centic or with a wedge-shaped fissure in the middle. Upon an old scallop shell from deep water ; rare. Hastings. 56. Hippothoa divaricata, Lamouroux. Colonies composed of oval zooecia arranged in single sequence and connected together by tubular prolongations. Lateral branches are given off at an open angle and unite with others ; the aperture is circular but with a narrow sinus below ; beneath the aperture runs a thickened, longitudinal, median ridge. Common upon shells and stones from moderately deep water. Hast- ings. 57. Hippothoa fiagellum, Manzoni. Similar in habit to the last species, but the zooecia are farther apart, the interval being usually equal in length to two zooe- cia, whereas in divaricata it is usually equal to the length of one. The aperture is egg-shaped, and there is no median ridge. Common. Hastings. 58. Rhyncopora bi-spinosa, Johnston. A species encrusting old shells, and one subject to several modifications in the region of the aperture, the margin of which is sometimes produced into two lateral and vertical processes ; at others, one of these may be bent across the aperture, or may become central. A fairly constant feature is a more or less spinous mucro rising from beneath the aperture. There is often too a large avicularium mounted upon a broad pedestal, taking the place of this mucro, and generally placed rather laterally. One specimen obtained is found enveloping a colony of the hydroid Hydraciinia echinata, itself encrusting the shell of a Nassa. The ooecia upon this specimen are particularly plentiful. Trawled ; rather rare. Hast- ings. EsCHARID.*: 59. Lepralia pollasiana, Moll. A hardy looking species encrusting rocks at low tide. Aperture large, more deeply arched than a semicircle ; front wall pit- ted. Common. Hastings. 60. Lepralia foltacea, Ellis and Solander. This species forms large masses of foli- ated and anastomosing laminae, the zooecia being disposed on both sides of the lamina?. The zooecia are ovate, and have large pores over the front wall. Aperture horse-shoe- shaped, with sometimes a slight prominence beneath. Habitat, rather deep water. Somewhat scarce. Hastings. 61. Lepralia pertusa, Esper. Encrusting old shells. Zooecia oval, with a circular aperture, of which the lower margin is slightly disjunct ; beneath is a process, tri-radiate in form ; wall of zooecium poriferous. It may be noted that young zooecia of Smittia cheilostoma before the development of the sinus closely re- semble the zooecia of this species. From moderately deep water; rather rare. Hast- ings. 62. Lepralia adpressa^ Busk. Colonies encrusting small shells, e.g. whelk, Natica, Trochus. The zooecia are ovate, pitted, and have a boss at either or both corners of the aperture. The latter is horseshoe shaped, the sides being slightly indented ; from moderately deep water ; somewhat rare. Hastings. 63. Lepralia nitidula, Hincks, MS. Hastings. 64. Porella (oncinna, Busk. A species encrusting shells and stones and showing much variation. The zooecia are coffin-shaped, or various in form, and has an opalescent lustre. The margin is often deeply sinuous, almost dove-tailed, and is perforated along the border. Aper- ture horseshoe shaped, with two spines in marginal zooecia and a prominence below. Very common. From moderate to deep water. Hastings. 65. Smittia lanasborovii, Johnston. Zooecia crystalline, oblong or coffin- shaped, with perforations in the front wall. Aperture nearly round and raised into a collar, with a small avicularium upon the lower lip. Not uncommon upon rock from deep water. Hastings. 66. Smittia reticulata, McGillivray. In this species there is a deep sinus in the lower lip, and instead of an avicularium there, as in the last species, there is a larger one below, pointing downwards and look- ing like a pendant from a neck. Above the aperture there are either two or three spines, and the margin of the zooecia is bordered with pits or vacancies. Hincks remarks upon an instance where two zooe- cia side by side have a single wide ooecium