CHAP. IV. } THE CRUISES OF THE ‘ PORCUPINE,’ 193 
from 30 to 250 fathoms, animal life was tolerably 
abundant. With other mollusca the following were 
found :—Trochus suturalis, Pu. (Sicilian fossil) ; 
Aenophora crispa, Kone (Sic. fossil) ; Cylichna 
striatula, ForBrEs (Sic. fossil); C. ovulata, Broccut 
(Sic. fossil); Gadinia excentrica, TrpERI; Scalaria 
Srondosa, J. Sowrersy (Sicilian and Coralline Crag 
fossil); Pyramidella plicosa, BRonNn (Sic. and Cor. 
Crag fossil); Actwon pusillus, ForBxs (Sic. fossil). 
The Echinodermata were abundant so far as indi- 
viduals went, but the number of species was small, 
and they were nearly all well-known Mediter- 
ranean forms. Cidaris papillata, Leskr, showing 
many varieties, but differing in no specific character 
from the many forms of the same species which 
range from North Cape to Cape Spartel in the 
ocean outside. The Mediterranean varieties of this 
species are certainly Ciduris hystrix, of Lamarck. 
I feel a degree of uncertainty about the pretty 
little Cidaris, described by Philippi under the name 
of C. affinis. Characteristic examples of it, which 
are abundant on the ‘Adventure’ Bank and along 
the African coast, look very distinct. They are of 
a beautiful deep rose red, the spines are banded 
with red and brownish-yellow, and come to a fine 
point, while those of C. papillata are usually blunt 
at the point, and frequently even a little expanded 
or cupped; and the portion of the interambu- 
lacral plates covered with miliary granules is wider, 
and two defined rows of body spines nearly of equal 
size lie up against the bases of the primary spines, 
over the alveole. These would appear to be cha- 
racters of specific value, but then again there are 
O 
