of South Devon and South Cornwall. 29 
spines is probably dependent, as in the case of M. Lacroixii, on 
situation. 
[Ilfracombe, on the Capstone Rocks. The specimens from 
this locality are destitute of the spines. | 
10. M. lineata, Linn., Alder, Northumberland Catal. p. 53, 
pl. Ss. fig. 1. 
Abundant between tide-marks. 
11. M. spinifera, Johnston. 
On stone, between tide-marks, Salcombe ; Goran (Peach). 
[Ramsay, Isle of Man, between tide-marks. | 
12. M. curvirostris, n. sp. Pl. VII. fig. 4. 
Cells oval, regularly disposed; aperture with a membranous 
covering; margin raised, slightly thickened, subgranular, 
with a short stout spine on each side near the top; ovicells 
globular, prominent, strongly frosted and silvery ; avicularia 
scattered, very large, raised, sloping upwards, with a pointed 
and curved mandible. 
On stone from 40 fathoms, ten or twelve miles south of 
Polperro. 
The most characteristic points in this species, which forms a 
neat and delicate network on the stone, are the regularly oval 
cells and the large and raised curvirostrate avicularia, which 
occur here and there, and are situated at one side of the cell 
near the top. The two spines project immediately below the 
ovicell. 
[M. craticula, Alder. 
Mr. Alder regards the Flustra lineata of Couch’s ‘Cornish 
Fauna’ as probably identical with this species; and, judging 
merely from the description and figure, I should have formed 
the same opinion. Mr. Peach, however, has kindly sent me a 
specimen of Memdranipora from Goran, which he believes to be 
the F. lineata of Couch; and this turns out to be the MW. spini- 
fera, exhibiting many of the characteristic club-shaped spines 
which bear the avicularia. As Mr. Peach is specially mentioned 
in the ‘Cornish Fauna’ as having supplied specimens of F. lineata 
from Goran, on which, amongst others, Mr. Couch founded his 
description, I now hesitate to identify this species with M. cra- 
ticula. It is not improbable that both forms may have come 
under his notice, but for the present this point must remain 
doubtful. 
