REPORT ON Till'. ( ilMMPEDIA. 139 



same subdivision of the genus as Verruca gibbosa. Ii is distind from this species in 

 the first place on account, of its greater smoothness ; neither the growth-ridges nor the 

 furrows are so distinctly visible as in the former species. The tergum and scutum in 

 general outline much resemble the same valves in Verruca gibbosa,bvd the articular 

 ridges are by no means so distinct. The rostrum and the immovable scutum are not 

 nearly so bullate as in the former species, and the apex of the rostrum is scarcely freely 

 projecting; on the other hand, the carina has the apex very strongly projecting. The 

 most interesting and certainly the most striking point of difference is the way in which 

 tin' rostrum and the carina articulate together: whereas in Verruca gibbosa the rostrum 

 is furnished with three very distinct teeth, which are placed in excavations of the other 

 valve, in Verruca nitida only one tooth, which corresponds to the strongest and upper- 

 most one of the other species, can be distinguished ; beneath this tooth the two valves 

 unite in a straight line. The immovable tergum and scutum do not form a perfectly 

 flat plane ; the apex of both valves is reflected, so that the surface of the valves is slightly 

 concave. The immovable scutum is furnished with a narrow kind of radius, and is 

 divided into two parts, which are placed angularly to each other and meet in a curved 

 line. The apex of the immovable scutum is distinctly beaked, and projects for a 

 considerable way over the immovable tergum. The hitter is divided into a middle pari 

 and two lateral parts as in the foregoing species. 



The only specimen is attached to what may be considered one of the tentacles of a 

 Pentacrinus. Its colour is white, its surface is not covered with membrane. 



The size of the specimen is 5 "5 mm. It was taken at Station 214, February 10, 1 875 ; 

 lat, 4° 33' N., long. 127° 6' E.; depth, 500 fathoms ; bottom temperature, 5°'3 C; bottom, 

 ( rlobigerina ooze. 



» 



Verruca sulcata, n. sp. (PI. VI. figs. 19 and 20). 



Shell dirty white; flat, especially at the side of the immovable scutum and tergum. 

 Surface with prominent growth-ridges; articular ridges of the scutum and tergum promi- 

 nent, as are also those of the carina and rostrum. Walls perpendicular to the surface of 

 attachment. Movable scutum rather large, with the apex pointed and projecting lively. 

 Upper articular ridge hardly distinguishable, middle articular ridge penetrates with a 

 sharp tooth between the two ridges of the tergum. Third articular ridge very prominent. 

 The slightly convex rostrum has four teeth, which alternate with three teeth of the carina. 

 and by means of which the valves are united together. 



This elegant little form also is represented by a single specimen only. It has 



the same general appearance as the former species. However, it is not difficult to 



distinguish it ; its scutum is relatively large, and the middle articular ridge terminates 



below in a very prominent tooth; the third articular ridge is very strongly developed. 



