OF NORTHUMBERLAND AND DURHAM. 203 
Under stones at low-water mark, rare. St. Mary’s Island.— 
A. H., 
Orper.—(Lus Ascrpres composes, Milne Edwards.) 
Famity. Borryiups, McLeay. 
127. APLIDIUM, Savigny. 
1. A. Ficus, Linn. ? 
Aplidium ficus, Forb. and Hanl. Brit. Moll. i. 11? 
Under stones among the rocks at Cullercoats, rare.—A. H. 
The specimen we refer, with doubt, to this species, formed an 
irregular lobed mass of a brownish colour, with the animals 
thickly disposed through it, without apparent pattern. Longest 
diameter nearly two inches. 
2. A. FALLAX, Johns. 
Aplidium fallax, Johns. in Loud. Mag. Nat. Hist. vii. 15, 
f. 4; Forb. and Hanl. Brit. Moll. i. 11. 
On sea-weeds, in pools between tide-marks, at Cullercoats, 
rare.—J. A. 
128. SIDNYUM, Savigny. 
1. S. rurBrInatum, Sav. ? 
Sydneum turbinatum, Flem. Brit. Anim. 469? 
A species, which we had always taken to be this, is not rare on 
our coast, but it differs from that figured in Forbes and Hanley’s 
“British Mollusca.” It is inversely conical, sometimes adhering 
by a narrow base, and is of an orange-red colour, with the animals 
vertically and concentrically arranged: their branchial apertures 
are eight-cleft. The masses are of different sizes, from a quar- 
ter to half an inch high, erect, and frequently clustered. 
129. POLYCLINUM, Savigny. 
1. P. aurantium, Jf. Edw. ? 
Polyclinum aurantium, Forb. and Hanl. Brit. Moll. 14, t. A, 
f. 3. 
On the under side of stones between tide-marks at Cullercoats, 
rather rare.—A. 
