REPORT ON THE RADIOLARIA. 1323 



latter, three free, radial spines, or simple wings, corresponding to the three basal feet of 

 Cortina, arise from the collar stricture between the small hemispherical cephalis and the 

 large, flatly conical thorax. Corocalyptra differs from Eucecryphalus, its ancestral 

 form, in the development of a flat and broad abdomen, which is a prolongation of the 

 thorax, and may be compared to the brim of a hat. 



1. Corocalyptra agnesce, n. sp. (PI. 59, fig. 3). 



Shell flatly conical or hat-shaped. Length of the three joints = 1:4:2, breadth = 2:8:12. 

 Cephalis hemispherical, with an oblique, small, conical horn of the same length. From the slight 

 collar stricture arise three slender, conical feet of equal length, twice as long as the apical horn, 

 nearly horizontally divergent. Lateral outline of the conical thorax straight, of the flatter abdomen 

 convex ; the smooth margin of the abdomen turned inwards. Network delicate, with subregular, 

 hexagonal pores. 



Dimensions. Length of the three joints, a 0'02, b 0'08, c 0'04 ; breadth, a 0'03, b 015, c O24. 



Halitat. Central Pacific, Station 270, surface. 



2. Corocalyptra elisabethce, n. sp. (PI. 59, fig. 10). 



Shell flatly conical, hat-shaped, very similar to the preceding species, but with different propor- 

 tions. Length of the three joints = 1:4:2; breadth = 1:7:10. Cephalis very small, with an 

 oblique horn of the same length. The three feet are of different sizes, the caudal odd foot being twice 

 as long as the two lateral, which are equal to the horn. Lateral outline of the campanulate 

 thorax convex, of the flatter abdomen less convex. Margin of the mouth flat. 



Dimensions. Length of the three joints, a 0'015, b 0'06, c 0'03 ; breadth a 0'02, b 014, c 0'2. 



Habitat. Tropical Atlantic, Station 347, surface. 



3. Corocalyptra emmce, n. sp. (PI. 59, fig. 4). 



Shell nearly conical, hat-shaped. Length of the three joints = 1:3:1, breadth = 1:5:7. 

 Cephalis hemispherical, with a straight horn of the same length. Feet of the collar larger than in 

 the preceding species, the two lateral smaller being directed upwards, the larger odd caudal down- 

 wards. Thorax slightly campanulate ; its hexagonal meshes two to four times as large as those of 

 the short, convex abdomen, which is turned inwards. 



Dimensions. Length of the three joints, a 0'02, b 0'09, c 0'03 ; breadth, a 01)25, b 013, c 017. 



Habitat. Central Pacific, Station 272, surface. 



4. Corocalyptra maryarethce, n. sp. 



Shell nearly conical, hat-shaped, very similar to the preceding species, but with much more 

 delicate hexagonal network, with thread-like bars. Length of the three joints = 1:7:2, breadth = 



