188 BULLETIN 93, UNITED STATES NATIONAL MUSEUM. 



ARCTIC AND WEST ATLANTIC. 



PACIFIC. 



BALANUS BALANOIDES CALCARATUS, new subspecies. 



Plate 45, figs. 3-3c; 4-4c. 



Type. -Cut. No. 32949, U.S.N.M., from Cold Bay, Shelikof Strait, 

 Alaska, collected by T. W. Stanton, 1904. 



The specimens are tubular, thin, very fragile, and grow in crowded 

 groups. When a group is broken, the break is usually through a 

 barnacle, so loosely are the compartments cemented. The length 

 varies from 9 to 20 mm., but fragments indicate that it attains over 

 double this size; diameter at orifice 5 to 8 mm. It is like the form 

 of B. crenatus from Albatross station 3232, except that the parietes 

 are smooth inside. The scuta are nearly flat, the apices not diverg- 

 ing. Articular ridge short, broadly reflexed, w T ith a callus between 

 its lower end and the adductor pit. Tergum with a long and 

 extremely narrow spur. Cirri not examined, as the body has been 

 destroyed by insects, the specimens being preserved dry. It 

 occurred with B. crena-tus, and therefore probably below low-water 

 mark. 



A single individual from Sitka (pi. 45, figs. 4-4<?) is conic, 

 strongly ribbed, with small, irregular marginal pores, most of them 

 filled up, at the basal margin. The watt is excessively thick and 

 the sheath much longer than in patelliform specimens from the 

 Atlantic. The scutum resembles that of the Shelikof Strait lot. 

 It is flat, the articular ridge strongly developed, basal and tergal 

 margins about equal. The tergum has a decidedly narrow tapering 

 spur. 



