72 BULLETIN 00, UNITED STATES NATIONAL MUSEUM. 



The cariual latus is broadl}' V-shaped, the carinal branch of the V 

 hir^er and curved. The umbones are recurved and project below and 

 beyond the carina. 



The peduncle is shorter than the capitulum, clothed with very large, 

 strongly projecting scales in seven rows of about twelve scales each. 



Length of capitulum 4-t, width 31 mm.; length of peduncle, 24 

 mm.; length of the carina 42, diameter at base 4,5 mm. (Fig. 28ff, h.) 



A half-grown individual from the type lot is figured to show the 

 true forms of the plates, the sutures l)etween the chitinous, uncalcilied 

 bordering portions being visible as white lines at this stage of growth. 

 In the drawing these sutures are represented by black lines. The 

 original outlines of the plates approach the contours of species of the 

 S. scalpellum group. (Fig. 28c.) 



The oldest specimen of the type lot measures — length of capitulum 

 43, of peduncle 34 mm. The peduncle has seven rows of about 

 seventeen scales each. 



This is the largest of the imperfectly calcified species of Scalpellum. 

 It is remarkable for the great reduction of the plates and their peculiar 

 forms. It is related to S. inarglnatiun Hoek, from off New Guinea, 

 but the plates are more reduced, the upper latera have a different 

 shape, and all the plates of the lower whorl differ somewhat in the two 

 species. 



Scalpellum edicardsi Gruvel, described from a single specimen 

 dredged b}^ the Talisman near the Azores in 4,255 meters, stands 

 close to S. dicheloplax, and further collections are needed to iv\\\j 

 elucidate their relations. The unique type of S. edwardsi has a 

 capitulum 25 mm. long. The plates of the lower whorl are com- 

 pletely calcified, while the scuta, terga, and upper latera are like 

 those plates in S. dicheloplax. In the smallest specimen of S. 

 dlclieloplax^ capitulum 28 mm. long, the lower plates are almost 

 wholly calcified (fig. 28c), approaching the condition of S. edtcardsi ; 

 but the umbo of the inf ramedian lateral plate is situated higher. The 

 chief difference is in the shape of the inframedian lateral plate. In 

 -6'. edirardsi"- the upper margiti of this plate is longest, concave, and 

 the basal part of the plate is extremely narrow — quite unlike the 

 shape in *S'. dicheloplaj-. Moreover, the carina of -5*. edwardsi is 

 described as with a flat roof bordered b}- two distinct but not ver}^ 

 pronounced lateral ridges, and with the sides especially well developed 

 in the upper part, while in the 3'oung as well as the adult S. dicJielojdax 

 the roof has a deep concave channel between two very high bordering 

 ribs, and the sides are not wider above than elsewhere. 



Whether the tj^pe of S. edivardsi is an adult form, and if not, what 

 subse(juent changes take place, are questions remaining to be ascer- 

 tained. It is evidently distinct specifically from -S'. dicheloplax. 



« Exp^d. Sci. du Travailleur et du Talisman, Cirrhipedes, p. 63. 



