ee es ee a a ee pa ee 
See nv . ics) 1 ‘ 
inhabiting the Estuary of the Dee. 201 
dida; and perhaps it is one of the most beautiful of this beau- 
tiful tribe. It mhabits the Mediterranean Sea, the south coasts 
of Europe and England,—the Menai Straits being the only 
northern locality known when the Ray Monograph was published. 
In July 1851, however, my friends Messrs. Byerley and Price, 
when on a visit’to Hilbre Island, each picked up a specimen of 
a new species of Antiopa possessing the crest of that genus, but 
in the tuberculated papille approaching still more closely to 
Proctonotus than did the first Antiopa. One of these was sent to 
Mr. Alder, but died before it reached him ; still, being a unique 
specimen, it was figured, and appeared in the Monograph under 
these adverse circumstances. Much as it resembled Proctonotus, 
the crest was with reason considered sufficient to distinguish it, 
and it was described under the name of Antiopa hyalina, the 
original species having in the mean time been renamed A. cris- 
tata—as I think, unfortunately, since the crest constituted a 
generic, and not a specific distinction. In August 1854 Mr. 
Byerley again met with a specimen of Antiopa hyalina within a 
few yards of the original spot. This was the first Mr. Alder saw 
alive, and it was a much superior specimen, more mature, and 
in altogether better condition than that figured, from which it 
differed in the greater length and more pointed character of the 
dorsal tentacles, the superior attenuation of the papille, and 
greater length of the tail. A careful drawing of it was made 
by Mr. Hancock, but too late to replace the one engraved for 
the Monograph. 
This remarkably local species has hitherto eluded search in 
every other spot, and is peculiar to Hilbre Island in the Dee ; 
and there, until the summer of 1859, it was the sole representa- 
tive of the genus. In July of that year, however, I was so for- 
tunate as to discover some fine specimens of Antiopa splendida 
(or cristata). These were such beautiful objects that I sent the 
largest to Mr. Alder, who informed me that even finer specimens 
occur in the Mediterranean. I look upon it, however, as the 
most lovely of the tribe, but one which has met with scant 
justice in that, for the most part, exquisitely-illustrated work. 
But it would perhaps be scarcely possible to delineate it satis- 
factorily: it deserves the name of hyalina even more than its 
congener. Mr. Moore, who visited Hilbre about a month after 
I had discovered Antiopa cristata, and who was with me on 
that occasion, upon looking into the rock-pool in which I had 
found them, saw an individual of that.species, and, with it, one 
with which he was not familiar. He brought it to Liverpool ; and 
on examination, it turned out to be another specimen of Antiopa 
hyalina. Thus this rare Nudibranch has been taken in the 
Ann. & Mag. N. Hist. Ser. 3. Vol. vi. 14 
