173 Mr. J. Alder on the British Tunicafa. 



like the plates of a Madrepore, while Forbes's species has the 

 individuals arranged circularly round the common centre. Both 

 the species described by British authors belong to the genus (or 

 subgenus*) Parascidia of Milne-Edwards, which has been sepa- 

 rated from Amarcecium on account of having eight lobes to the 

 branchial aperture, none of the other genera of compound Tunica- 

 ries having more than six. I propose naming these two species 

 Parascidia Flemingii and P. Forbesii. The Sidnyum turbinatum 

 remains yet to be recognized. 



Parascidia flabellaia, n. sp. 



Common bodrj elongate, lobulated, transparent, consisting be- 

 low of a very much produced peduncle, which is divided above 

 into several oblong branches, variously lobed, forming a some- 

 what fan-shaped expansion at the free end ; many orange masses 

 or spots in the interior give an orange hue to the whole. Indi- 

 viduals elongate. Branchial apertures eight-lobed, tinged with 

 orange. Postabdomen longish, linear, and rather thin. The 

 whole mass is prettily and minutely speckled with orange. 



The above account of a very interesting little Parascidia is 

 extracted from theHev.T.Hincks^s manuscript notes of Tunicata 

 obtained in Salcombe Bay in 1848, kindly placed at my disposal. 

 Mr. Hincks met with this species hanging about a Cellularia in 

 little orange transparent tufts. There can be no doubt of its 

 distinctness from any species yet described. 



Distoma vitreum, Sars. 



Distomum vitreum, Sars in Nyt Mag. for Naturv. vol. vi. p. 154. 

 Christiania, 1851. 



Common body greyish-white, hyaline, subcartilaginous, clavate 

 or fusifoi'm, adhering by a narrow base. Individuals white or 

 yellowish, irregularly disposed. Branchial and anal apertures 

 each with six blunt lobes. Abdomen ovate-oblong, united to the 

 thorax by a thiekish peduncle ; the stomach brownish and lon- 

 gitudinally plicated. Length of mass a quarter to half an inch. 



A cluster of specimens of different sizes (mostly young), ad- 

 hering to the stem of a Zoophyte, was dredged by Mr. Norman 

 in the Channel Islands. 



Botrylloides sparsa, n. sp. 



Common body rather thick, encrusting, semitransparent, of a 

 yellowish-brown colour. Individuals rather small, yellowish- 

 brown, thickly sprinkled with dark brown spots, with a circle of 



* Prof. Milne-Edwards makes both Amarcncimn and Parascidia sub- 

 genera of Polyclinum. I prefer considering tliem genera. 



