CR USTA CEA—CIRRIPEDIA . 



371 



direct cementation of the calcareous corona {Balaniis) or by a 

 fleshy peduncle (Lepas) to a variety of substratum, rock, wood, 

 molluscs, other Crustacea, marine plants, etc. They are all marine, 

 living abundantly in the shore zone, and extending to the depth of 

 2,000 fathoms. The fossil genera of America include I., Lepi- 

 docoleiis Faber (Ordovicic-Devonic) of two rows of vertical, 

 overlapping plates; Examples: i. L. jamesi (Hall & Whitfield), 

 Cincinnati group of Ohio ; 2. L. sarlei Clarke, Rochester shale of 

 New York (Fig. 1671) and 3. L. polypetalus Clarke, from the Hel- 



FiG, 1673. Balanus concavus Bronn. a^ lateral view of a complete specimen, X 

 Yz ; b, basis of same ; <:, interior of rostrum; d, interior of lefi lateral compartment 

 [lateralium^ ; e, interior of rigAt lateral compartment ; f, interior of carina ; g, in- 

 terior of left carino-lateral compartment {carino-lateralium) ; h, interior of rz^/^/ carino- 

 lateral compartment [carino-lateralium) ; i, J, lateral and end view of scuta and tei'ga, 

 conjoined; k, I, exterior and interior of left scutum; m, n, exterior and interior of 

 right scutum; o,p, exterior and interior of right tergum ; q, r, exterior and interior 

 of left tergufu. All reduced one half. (After Martin, Md. Geol. Surv., Miocene.) 



derbergian of New York. II., Turrilepas Woodw. (Cambric-De- 

 vonic) : four to six columns of overlapping scales; Examples: 4. T. 

 devonica Clarke; 5. T. squama Clarke, both of the Hamilton shales 

 of New York. III., Strohilepis Clarke (Devonic) of four columns 



