THE BARNACLES IN THE U. S. NATIONAL MUSEUM. 29 



towiird the ventral border. The rostrum is decidedly better developed 

 than ill adults. It is ol^lont^ and parallel-sided, with truncate apex in 

 the larger examples, but is wider near the apex and tapei's downward 

 in the smallest specimen. The scutum is somewhat narrower than 

 in adult regli.nn. These young' specimens are from the followino- 

 stations: 



Cat. ^o.-lOlS"!^ Albatross Station 2575, north latitude 41^ 07', west 

 lonoitude 65^ 26' 30", in 1,710 fathoms: temperature, 37.1^ F. No. 

 L07S1, Albatross Station 2533, north latitude 40" 16' 30", west longitude 

 t)7 26' 15", in 828 fathoms; temperature, 38.7° F. No. 8637, Alba- 

 t/'o-s.^ Station 2228, north latitude 37° 25', west longitude 73° 06', in 

 1,582 fathoms: temperature, 36.8'^ F. 



SCALPELLUM REGIUM LATIDORSUM, new subspecies. 

 Plate II, figs. 2, 3, 7. Plate IV, figs. 10, 11, 12, 14. 



Tt/j)e.—Csit No. 8632, U.S.N.M. 



Type-locality. — Albatross Station 2222, north latitude 31)° 03', west 

 longitude 70° 51', 1,537 fathoms. 



Other localities.— ^o. 9058, Station 2042, north latitude 39° 33', west 

 longitude 68° 27', 1,555 fathoms. No. 9057, Station 2041, north lati- 

 tude 39° 23', west longitude 68° 25', 1,608 fathoms. Station 2210, north 

 latitude 39° 37' 45", west longitttde 71° 18' 45", 991 fathoms. 



The capitiilum resembles that of S. regiuni in shape and the general 

 arrangement of the plates. It differs by the larger size of the infra- 

 median latera, and by the shape of the carina, which has a flat roof bor- 

 dered by rounded ridges (as shown in Plate II, fig. 7, a diagram of the 

 carina in transverse section). It is wider than the carina of ^S*. regium. 

 A small triangular chitinous appendage extends upward bej'ond the 

 lunbo of the carinal latus. The thin cuticle is quite sparsely hairy. 



Length of the capitulvun, 40, of peduncle 19. mm.: length of carina 

 38; diameter at base 9 mm. 



This form was taken only at several adjacent stations southeast from 

 Nantucket. A series of about a dozen specimens was examined, the 

 capitula from 11 to 40 nnii. long. 



In those from Station 2042 the inframedian latera are higher than 

 wide, with the apices curving slightly toward the scuta. In the speci- 

 mens from Station 2041 the aj:)ices are more strongly curved. 



A form closely related to 8. r. latldorsuiu, said to be from a Pacific 

 station, represented by a series of over a dozen examples, may be 

 described here. (Plate II, figs. 9, 10, natural size.) It is No. 32916, 

 U.S.N.M., from Albatross Station 3342, north latitude 52° 89' 30", 

 west longitude 132° 38', off British Columbia, in 1,588 fathoms. 

 This form differs from S. regium, latidorsiini chiefly In' the narrower 

 roof of the carina and the larger chitinous appendages above the 



