REPORT ON THE RADIOLARIA. 1719 



1. Conchasma radiolites, n. sp. (PI. 123, fig. 5). 



Shell nearly spherical, somewhat compressed on both sides ; the dorsal valve smaller, flatter 

 and shorter than the ventral valve. In the half sagittal perimeter of the shell twenty to twenty-two 

 pores, in the half frontal perimeter twelve to fourteen, in the half equator eighteen to twenty. 

 All pores nearly of the same size, circular, hexagonally framed, scarcely as broad as the bars. The 

 two horns of the hinge are four-sided pyramidal, of different sizes ; the ventral horn (of the larger 

 valve) two to three times as long as the dorsal horn (of the smaller valve) ; the latter twice as long 

 as a pore. 



Dimensions. Length of the shell 016, height 015, breadth 014. 



Habitat. Antarctic Ocean, Station 154, depth 1800 fathoms. 



2. Conchasma sphcerulites, n. sp. (PI. 123, fig. 6). 



Shell nearly spherical, somewhat compressed on both sides, the frontal diameter therefore 

 somewhat shorter than the two others. Both valves nearly of the same size, hemispherical, their 

 borders smooth, twice as broad as the largest pores. In the half sagittal perimeter of the shell 

 twenty-eight to thirty pores, in the half frontal perimeter twenty to twenty-two, in the half equator 

 twenty-four to twenty-six. Size of the pores increasing from the borders towards the top of the 

 valves. One series of very small pores along the frontal free margin of each valve. Pores roundish- 

 polygonal, three to four times as broad as the bars. The two horns of the hinge are of equal size, 

 four-sided pyramidal, and twice as long as the larger pores. 



Dimensions. Length of the shell 018, height 018, breadth 016. 



Habitat. Antarctic Ocean, Station 152, depth 1260 fathoms. 



3. Conchasma hippurites, n. sp. 



Shell nearly spherical, scarcely compressed. The frontal diameter equal to the two others. 

 Both valves equal. In the half sagittal perimeter of the shell thirty-two to thirty-four pores, in 

 the half frontal perimeter twenty-four to twenty-six, in the half equator twenty-six to twenty-eight. 

 All pores of nearly equal size, circular, polygonally framed, twice as broad as the bars. The two 

 horns of the hinge are large, three-sided pyramidal, the ventral horn twice as long as the dorsal, and 

 four to six times as long as one pore. 



Dimensions. Length of the shell 0'22, height 0'21, breadth 0'2. 



Habitat. Antarctic Ocean, Station 157, depth 1950 fathoms. 



Subfamily 2. CONCHOPSIDA, Haeckel. 



Definition. C oncharida with the lateral margins of the two valves dentate, the 

 teeth of both catch one into another. 



