474, Rev. T. Hincks’s Catalogue of Zoophytes. 
culty. The cells, however, are sufficiently well marked. They 
are stout, sessile, of equal size throughout, somewhat quadran- 
gular, opake, and of a very dark-brown colour when dried. This 
seems to be the form which Mr. Alder has identified with the 
Avenella fusca of Dalyell (Northumberland Catal. p. 69). The 
latter, however, I have no doubt, is a distinct species. Its cells 
are smaller and more slender, with a tendency to assume a bent 
form. They taper slightly both towards the base and the upper 
extremity ; and the opacity is due to a peculiar constitution of 
the ectocyst, resembling that which Mr. Busk has described in 
the case of Farrella gigantea (Microscop. Journ. vol. iv. p. 98). 
The creeping fibre is also perfectly simple. I have specimens 
from Professor Wyville Thomson, which agree in all respects 
with Sir John Dalyell’s figure. 
Avenella gigantea differs from the A. fusca in size and in the 
shape of the cell. 
Mr. Busk unites. Avenella with Farrella. But perhaps the 
species with sessile and opake cells and numerous tentacles 
are entitled to distinct generic rank. 3 
Order PHYLACTOLAZMATA, Allman. 
Suborder Pedicellinea, Gervais. 
Fam. Pedicellinide. 
Prpiceiuina, Sars. | 
1. P. echinata, Sars. 
Very common : between tide-marks; on Vesicularia from the 
Brixham trawl-stuff,; &c. : 
2. P. Belgica, Van Beneden. 
Exmouth, on weed in rock-pools. 
[Filey, between tide-marks ; Llandudno. | 
8. P. gracilis, Sars. 
Common: under stones, Salcombe; Torbay (8 fathoms), &e. 
[Lamlash Bay; Filey; Llandudno; Ramsay, Isle of Man.] 
Suborder Lo phopea, Allman. 
Fam. Plumatellide, Allman. 
PLUMATELLA, Lamarck. 
P. repens, Linn. 
Stoke, near Plymouth. 
I have not had the opportunity of investigating the freshwater 
Polyzoa of Devon and. Cornwall; and none are included in 
