MUREX. 495 
is the “rugged form” of the M. nebula of the ‘ Brit. Moll. 
vol. i. p. 477 :—fig. 7. of pl. 114 is this form and our M. 
Ginannianus. 
I might have generalized in this species, but I am obliged 
to give a somewhat more detailed account of it than usual, 
as it is the standard of comparison with the two next spe- 
cies, with which it has been considered identical by some 
conchologists. 
I have myself dredged this species in the lJaminarian 
zone off Budleigh Salterton. A larger variety is taken occa- 
sionally in the deeper waters of the coralline zone, which I 
am inclined to think may turn out a distinet species. It 
appears in ‘ Brit. Moll? vol. i. p. 478, as var. pyramidata of 
Mangelia nebula. The organe générateur is precisely similar 
to that of Murex gracilis. 
M. nesura, Montagu. 
Mangelia nebula, Brit. Moll. ui. p. 476, pl. 114. f.7,8, 9; (animal) 
plot R.dofe 
This animal has the closest alliance with M. Ginannianus, 
therefore only the very doubtful and almost mappreciable 
variations will be mentioned. In this species the eyes appear 
larger and the tentacula proportionately shorter than in 
M. Ginannianus. The general aspect of the shells of the two 
species appears to afford even better specific distinctions than 
the animals. In August 1849, I dredged in Littleham Cove, 
near Exmouth, in the laminarian zone, several specimens 
both of the M. Ginannianus and M. nebula at the same 
haul; they proved lively and afforded a good examination 
for some hours; and the differences between them with 
respect to the shells are, that the M. Ginannianus is less 
slender, the aperture more patulous, and the colour of 
a uniform yellow, whilst that of IM. nedula is much darker, 
and shows a still darker spiral band in the sutures. The 
animals also differ: the M. Ginannianus has the ground 
colour of a very pale yellow-brown, suffused with a tinge of 
light red, and the flakes with which the whole body is aspersed 
have a light sulphur tinge; whereas in M. nebula the ground 
