THE SESSILE BARNACLES. 31 



VERRUCA FLORIDANA, new species, 

 Plate 4, figs. 1 to Ic, 2, 3. 



Type. Cat. No. 1901, A.N. S. P. Cotype,Cat. No. 48095, U.S.N.M. 



Type-locality. South of Key West, Florida, in 90 fathoms, on dead 

 shells of Valuta dohrni, living Pleurotoma albida, and on Dorocidaris 

 spines. Eolis expedition, 1911. 



The barnacle is white, about as wide as long, varying from square 

 to approximately circular in outline; the opercular plates are quite 

 flat, and usually slope at a low angle with the plane of the base. 

 The plates of the wall are rather thin, and are beveled to an edge 

 at the base, with no trace of inflection. 



The movable scutum has three articular ridges, the th.ird or cres- 

 centic ridge extending to the basitergal angle. They are parted by 

 two wide, shallow furrows. The rest of the surface has rather 

 widely spaced impressed lines parallel to the rostral border, and cut 

 by one (in the type) or sometimes by two or three curved radial 

 furrows, which do not extend to the apex of the plate (and therefore 

 are not present in young individuals). When detached, this plate 

 is seen to have two low, wide teeth on the tergal border, between 

 the apex and the rostro- tergal angle. Internally the plate is quite 

 smooth, gently concave in the median part. 



The movable tergum is nearly square, the carinal border, however, 

 being somewhat longer than the occludent border. It has three 

 strong, well-raised articular ribs, the rest of the plate being sculp- 

 tured with sunken lines parallel to the carinal margin of the plate and 

 rather widely spaced. The interior face is smooth. 



The carina has three wide, low radial ribs from apex to rostral 

 suture, where they terminate in teeth interlocking with those of the 

 rostrum, producing a strongly zigzag suture. Parallel with the upper 

 rib there is an inconspicuous, very narrow riblet along the tergal 

 border. 



The rostrum has two principal ribs articulating with those of the 

 carina. There is also a ledge along the scutal border sculptured 

 with several small, curved radial riblets, terminating on the scutal 

 border. 



The fixed scutum has a small, recurved apex. The surface is 

 divided into (1) a large triangle bounded by lines connecting the 

 apex and basal extremities, which would be termed the paries in a 

 Balanid, and which has only irregular sculpture consequent upon its 

 base of support; (2) a somewhat smaller triangle above the former 

 one, with its base against the rostrum, sculptured with vertical, 

 spaced lines, and sometimes some radial riblets near the rostrum; 

 (3) a small, densely lineolate area between the apex and the movable 

 scutum ; and (4) a very small, vertically lineolate, radiif orm triangle 

 toward the fixed tergum. Inside there is a rather small adductor 



