AMOUROUCIUM. 15 



tinguisliable by the naked eye, but wlien the surface is examined 

 with a lens, a number of little holes, ranged in linear series, are 

 seen ; the mouths of the animals united in a common mass 

 grouped round one or many systems, each opening into a common 

 cloaca ; tegument coriaceous." — Milne-Edwards. 



Mr. Alder finds a species, which seems to be a pale, fuscous, 

 yellow variety of this, at Cullercoats. 



AMOUROUCIUM, Milne-Edwards. 



Mass lobed or encrusting, sessile or pedunculated, fleshy or 

 cartilaginous, composed of many systems, more or less circum- 

 scribed, each having a central cavity; the individuals, more or 

 less numerous, placed at unequal distances from the common 

 centre ; their anal orifices open into a common cloaca ; bran- 

 chial orifice six-rayed ; post-abdomen not pedunculate, but fol- 

 lowing superior abdomen, as in Aiilidium. [See pi. B, fig. 4.] 



1. A. PROLiFERUM, Milne-Edwai'ds. 



Mem. Asc. Comp. p. 287, pi. 1, fig. 3, and pi. 3, fig. 2. 



Yellowish or red fleshy masses, sometimes encrusting, some- 

 times lobed, with orange elongated spots on their upper surface. 

 Individuals with a red thorax. 



" Belfast Bay," W. Thompson, in Ann. N. Hist. vol. xiii. 

 (1844) p. 485. " Not uncommon in Cornwall," Mr. Alder. 



2. A. NoRDMANNi, Milne-Edwards. 



Mem. Asc. Comp. p. 289, pi. 1, fig. 5. 



" Thick encrusting masses, broader than high, of a light rose- 

 colour, tinged with yellow towards the base. Systems few, and 

 usually arranged in a single row, so as to represent a more or less 

 elongated ellipsoid, usually several in a mass, and distinctly cir- 

 cumscribed. The oral opening of these Ascidians is but slightly 

 prominent, and the lobes of the membranous border are obtuse 

 and white, so as to constitute a circle of six white rounded spots 

 around the mouth, contrasting with the general rose-colour ; the 

 tegumentary tissue is yellowish, and the prevailing rose-colour 

 depends on the tint of the thoracic portion of the bodies of the 

 Ascidians."— M.-E. 



At Falmouth, Mr. Alder. 



