196 BALANID.E. 



like points ; scuta with their exterior surface either plain, or with 

 radiating lines formed of hood-like projecting points. 



Far. (6) spinosus (Gmelin) (PI. 1, fig. i) : globulo-conical or cylin- 

 drical ; shell rather thin, with long, upcurved, nearly cylindrical, very 

 sharp points; colours very pale ; attached to other specimens, and to 

 Lepas anatifera. 



Far. (7) coccopoma (PI. 1, fig. d; PL 2, fig. \f \l, lo) : globulo- 

 conical; orifice small, rounded ; walls generally smooth, thick ; intense 

 rose-colour, sometimes most faintly striped longitudinally with varying 

 shades of pink ; radii tinged ivith purple ; scutum sometimes as in 

 var. communis, sometimes with its basi-tergal corner much cut off , with 

 the adductor ridge prominent, the pit for the depressor muscle deep, and 

 the articular ridge broad and hooked ; tergum sometimes as in var. 

 communis, sometimes with a broader spur, placed nearer to the basi- 

 scutal corner of the valve. 



Var. (cS) concinnus (PI. 1, fig. e : PI. 2, fig. \g) : globulo-conical ; 

 walls finely ribbed; dull purple, tinged and freckled with white; 

 scutum, with a broad, hooked, articular ridge, with an extremely sharp 

 plate-like adductor ridge, and with a cavity, bordered by a plate, for 

 the rostral depressor muscle ; tergum as in var. 1. 



Var. (9) intermedins : radii with their summits slightly oblique ; 

 parietes pale blueish-purple, with narrow dark purplish-hive longi- 

 tudinal lines; sheath with the internal surface of the rostrum and 

 lateral compartments much darker colored than the internal surface of 

 the carina and carino-lateral compartments ; scuta and terga as in 

 var. communis. 



Var. (10) occator (PI. 1, fig. k : PI. 2, lb): radii with their sum- 

 mits slightly oblique ; parietes smooth, or ribbed, or spinose ; very pale 

 blueish-purple, with narrow darker longitudinal lines ; sheath with the 

 internal surface of the rostrum and lateral compartments dull blue, 

 whilst the corresponding parts of the carina and carino-lateral compart- 

 ments are white ; scuta with small, sharp, hood-formed points, arranged 

 in straight radiating lines ; terga with the spur placed at either its 

 own width, or less than its own width, from the basi-scutal angle. 



Var. (1 1) d'Orbignii {Chenu) (PL 1,'fig. /: PL 2, \m, \n) : radii with 

 their summits oblique, and the orifice of the shell rather deeply toothed ; 

 shell conical or tuhulo-conical, s?nooth, or rugged ; colour dull j>urplish- 

 lilac, with the tips of the parietes and a band along one side of the 

 radii quite white ; sheath rather darker at the rostral than at the ca- 

 rinal end ; scuta as in var. 1 ; terga as in var. occator. 



Habitat. — West coast of Africa, on mytili: Madeira, on rocks : West Indies : 

 Cape of Good Hope, on a patella and on kelp: mouth of the Indus: East 

 Indian Archipelago : Sydney, Australia, attached to Lepas anserifcra, adhering 

 to a floating cane : Peru ; Galapagos Islands ; West Mexico ; California. 

 Extremely common on ships'-bottoms arriving from West Africa, India, and 

 China, often associated with B. amphitrite. 



Fossil— died Crag, England ; Mus S. Wood and J. de C. Sowcrby.— Tou- 

 raine (?) ; Mus. Lyell. 



General Remarks. — This, the first species of Balanus, is, perhaps 

 with the exception of B. amphitrite, the most difficult and variable in 



