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, Ph. (Sicilian fossil); 

 Xenophora crispa, Konig (Sic. fossil) ; Cylichna 

 striatula, Eorbes (Sic. fossil) ; C omilata, Brocchi 

 (Sic. fossil) ; Gadinia excentrica, Tiberi ; Scalaria 

 frondosa, J. Sowerby (Sicilian and Coralline Crag 

 fossil) ; JPyramidella plicosd, Bronx (Sic. and Cor. 

 Crag fossil) ; Actceon pusillus, Forbes (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, Leske, 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 Cidaris hystrix, of Lamarck. 

 I feel a degree of uncertainty about the pretty 

 little Cidaris, described by Philippi under the name 

 of C. affiuis. 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 alveolae. These would appear to be cha- 

 racters of specific value, but then again there are 



o 



