THE BARNACLES IN THE U. S. NATIONAL MUSEUM. 51 



Thccai'iiml latus is irregularly triangular, })r()j('('tino- a little ))(\V()nd 

 and hplow tho carina. Th(^ two latora meet in a \'er3' shoi-t suture 

 below the carina. Umbo .slightly recurved at the })ase of the carina. 



The peduncle is very short, with 10 rows of large scales, about (} 

 scales in a row. 



Length of capituluni about 18.5, width T mm.; length of peduncle 

 5 mm. ' 



The type-specimen was broken in the dredge across the terga and 

 upper part of the scuta. The species is notable for the shape of the 

 upper latus, which is unlike any known form of the same group. The 

 very small, nodule-like rostrum, visible only between the apices of 

 the rostral latera, is also highly characteristic. 



A young example (fig. 16 e) occurred with the type and is here illus- 

 trated to show the changes which take place with age. The upper 

 lateral plate is normal in shape, without the basal notch of the adult. 

 This would be anticipated from observing the growth-lines of the lat- 

 ter. The rostrum is relatively better developed l)ut formed as in the 

 adult tj\)e. The inframedian lateral plate is somewhat less individual- 

 ized than in the t3^pe. Length of capituluni 7, breadth 3.1 mm. 



S. recurvlter(/u/n Gruvel, from near the Azores, is a closely allied 

 form, difl'ering bv its strongly recurved terga, the somewhat difl'er- 

 ently shaped upper latus, and the hairy peduncle and carina. (Fig. 16.) 



SCALPELLUM GRACILIUS, new species. 



Ti/jje.~Cat. No. 32863, U.S.N.M. 



Type-locality. — Albatross Station 2678, off Cape Romain, South 

 Carolina, north latitude 32 ' 40', west longitude 76^ 10' 30", in 731 

 fathoms; l)ottom tem[)erature 38.7^'. 



The capitulum is narrow, its length more than double the width; 

 both ventral and dorsal margins are slightly convex; composed of 11: 

 full}^ calcilied plates; covered with a thin smooth cuticle. Sutures 

 linear. The plates have slight growth lines, and a few barely per- 

 cepti])le radial strife. 



The scutum is fully twice as long as wide; the occludent margin 

 convex, except near the base, where it is slightly concave. Lateral 

 margin slightly sinuous, subparallel to the occludent margin. Basal 

 margin passing into the lateral in a regular curve. The apex is a little 

 incurved and acummate. 



The tergum is much longer and wider than the scutum, triangular. 

 The occludent margin is slightly convex, basal margin straight, and 

 the carinal margin is very weakly sigmoid, nearly straight. The apex 

 is erect. 



The carina is regularh^ curved, with the apex terminal. The roof 

 is strongly and evenly convex, cur\ing into the sides, which are rather 



