112 THE VOYAGE OF H.M.S. CHALLENGER. 



furrowed longitudinally. Upper latus large, hexagonal. Infra-median latus large, 

 wine-glass shaped. Scutum almost triangular. Peduncle cylindrical, with minute and 

 very prominent scales. 



This species is extremely characteristic through the form of its scutum and of its 

 upper latus. It is represented by a single specimen only. 



Capitulum of an elongate-oval shape, flat, consisting of thirteen valves only. The 

 valves show distinct lines of growth, and are separated from each other by rather broad 

 chitinous interspaces. 



Scutum triangular, caused by the lateral margin being almost a prolongation of the 

 .short basal margin. Occludent margin arched. Tergal margin rather long, a triangular 

 portion is described at the lateral extremity of the tergal margin by this margin, and 

 by the uppermost part of the lateral margin. This triangular portion penetrates 

 between the upper latus and the tergum, where it is received into a small excavation. 

 Umbo of the scutum at the apex, which is slightly turned upwards. 



Tergum triangular, with a not very long occludent margin. Carina! margin slightly 

 arched, scutal margin slightly hollowed out. A triangular portion at the basal angle 

 penetrates between the upper latus and the carina. 



Carina not very strongly and simply bowed. Eoof flat, not increasing much in 

 width from the upper to the lower extremity; bordered by distinct ridges, hence 

 the surface appears longitudinally furrowed. Sides at right angles with the roof, not 

 very wide, but of the same width over the whole length of the carina. 



Upper latus irregularly hexagonal, rather large. Its umbo is seated a little above 

 the middle of the scutal margin. 



Rostral latus irregularly quadrangular. Scutal margin almost straight, lateral 

 margin describing an Shaped hue, rostral margin straight, basal margin straight also. 



Infra-median latus having the form of a wine-glass. The foot is small, triangular, 

 and the umbo is seated at the base of a much larger and wider portion. 



Carinal latus irregularly quadrangular. Umbo at the foot of the carinal margin, slightly 

 protuberant beyond the edge of the carina. Carinal margin hollowed out, upper margin 

 short and oblique. Lateral margin hollowed out, basal margin well-developed. 



Length of the capitulum, 15 '5 mm. 



Peduncle short, 5 "5 mm., covered by very small and numerous calcareous scales, placed 

 in not very regular rows. On some of the longitudinal rows thirteen or fourteen scales 

 may be distinguished. The scales have very prominent and rounded free edges. The 

 chitin of the peduncle may everywhere be seen between the scales. 



Structure of the animal not studied ; complemental male not observed. 



The species was taken at Station 218, March 1, 1875 ; lat. 2° 33' S., long. 144° 4'E. ; 

 depth, 1070 fathoms; bottom temperature, 2° - l C. ; bottom, Globigerina ooze. 



