THE BARNACLES IN THE U. S. NATIONAL MUSEUM. 19 



At Station 2767, off the east coast of Patagonia, they grow larger, 

 the eapituhnn reaching a length of 18 to 20, peduncle 16 to 2<) nnn. 

 long, and the umbo of the inf ramedian lateral is usually flattened. A 

 single individual from Station 2758, farther north, has the umbo 

 similarly flattened. 



S. putagonlcwih is remarkable for the imperfect calcification of 

 the valves in the adult stage. In other respects it resembles S. 

 i<calpeUu7n. 



GROUP OF SCALPELLUM CALIFORNICUM. 



SCALPELLUM CALIFORNICUM Pilsbry. 



1907. ScalpeUum calif ornicuni Pilsbry, Bulletin of the iUireau ni Fisheries, 

 XXVI, p. 196, pi. VI, figs. 8, 13. 



Tyj)e.—Cat. No. 32811, U.S.N.M. 



Locality. — Vicinity of Montere}'^ Ba}-, C^alifornia, inloto 86 fathoms. 



SCALPELLUM OSSEUM Pilsbry. 



1907. Scalpellum caUforulcum (jssenni Pilsbry, Bulletin of the Bureau of Fish- 

 eries, XXVI, p. 196, pi. VI, fig. 7. 



Ti/pe.— Cat. No. 32113, U.S.N.M. 



Ti/pe-locality. — Alhatross Station 4451, off Point Pinos Light, 71 

 fathoms. 



Other localities.— ^o. 32910, U.S.N.M., Alhatross Station 2906, off 

 southern California, north latitude 34° 23' 30", west longitude 120° 

 19' 30", in 96 fathoms, bottom temperature 55.5°. 



The capitulum is oblong-rhombic, with the occludent border straight 

 or nearly so; dorsal border moderately convex; upper border oblique 

 and a little concave. It is composed of 14 fully calcified valves, joined 

 by narrow sutures, covered with a thin cuticle, sparsely hairy on the 

 sides, more profusely so dorsally. The valves are weakly sculptured 

 with widely spaced wrinkles along lines of growth. 



The scutum is half the total length of the capitulum, and fulh^ 

 twice as long as wide, with parallel occludent and lateral margins and 

 acute, erect, apex, which does not project from the occludent outline. 

 The umbo is removed a short distance from the apex. The basal 

 margin is oblique and straight. The occludent half of the plate shows 

 some ver}' inconspicuous radial stri*. 



The tergum is triangular, nearly 1^ times the length of the scuta. 

 The occludent and scutal margins ai'e straight, the carinal margin a 

 little irregular or convex; apex erect. 



The carina is weakly curved, with apical umbo. The roof is con- 

 vex, quite wide toward the base, and bounded b}' low ribs. The 

 sides are well developed, divided into two areas by a low curved rib- 

 let which defines the division into intraparietal and parietal portions. 



