130 Mr. 8. O. Ridley’s Contributions to the 
At the same time the spiculation is essentially that of Huni- 
cella, the genus to-which Verrill refers Gorgonia verrucosa 
and numerous other Atlantic species. 
Hab. Mediterranean (sper). 
It is from the leathery or parchment-like appearance of the 
cortex when dried that the specific name pergamentacea has 
been taken. Itseems to me important to distinguish a species 
which, though not uncommon, has hitherto been confounded 
with another form. 
Fam. Gorgonellide. 
Nicella dichotoma. 
Scirpearia dichotoma, Gray, P. Z.S. 1859, p. 481. 
Nicella mauritiana, id. Cat. Lithophytes Brit. Mus. p. 40, fig. 12. 
Some good-sized specimens have been received from Mr. 
de Robillard ; the largest measures 340 millim. (134 inches) 
in height from the (dead) base, and 240 millim. (93 inches) 
in maximum diameter. Studer (M.B. Ak. Berlin, 1878, p. 660, 
pl. v. fig. 31) seems by his figure to have wrongly identified the 
species. Theoriginal specimens have fortheirspiculationa dense 
cortical layer of small double heads, and a subjacent layer of 
longer densely tuberculate cylindricals or fusiforms, having 
a median bare space more or less strongly indicated. ‘The 
colour is variable ; that of one specimen varies from ochreous 
yellow to dull flesh-colour; that of another is dirty white. The 
shape of the verrucee varies considerably, according as they 
are open or closed: in the former condition they are rectan- 
gular at the apex, as seen from the anterior or posterior 
sides of the frond, while in the latter they usually appear 
conical, with rounded apices, when viewed in the same way. 
Their basal diameter may vary from 1°25 to 2°25 millim. in 
the closed condition. The axis is strongly penetrated with 
carbonate of lime. 
It appears to me that the earlier specific name should be 
maintained. 
Hab. Mauritius, 80 fathoms. 
_ Fam. Trinellide, Gray. 
PARISIS. 
This genus is allied to Trinella, Gray ; but the latter has 
no true spicular verruces; while in Pardsis the spicules, the 
subjacent ones of which have the same general character as 
in Trinella, ascend into and support the verruca. 
The genus has not been hitherto recorded as occurring out 
