REPORT ON THE RADIOLARIA. 21 



Dimensions. Diameter of the central capsule - 4 to 0'8, of the nucleus 0'02 to - 05, of the 

 calymma 1 to 5 mm. 



Habitat. Cosmopolitan ; common in all warmer seas ; Mediterranean, Atlantic, Indian Ocean, 

 Pacific, mainly between lat. 40 N. and lat. 40 S. ; surface. 



6. Thalassicolla maculata, n. sp. (PI. 1, fig. 4). 



Spherical body in the central part opaque, black or dark coloured, in the periphery semi-trans- 

 parent, spotted. Central capsule compact, yellowish, opaque, with a thick and firm, very elastic 

 membrane, areolated by polygonal, punctated figures resembling cells. Diameter of the central 

 capsule about twice that of the nucleus, one-third to one-fifth that of the jelly-cover. Nucleus thin- 

 walled, with one large spherical nucleolus. Protoplasm of the central capsule contains innumerable 

 very small, hyaline, spherical vesicles of equal size (or vacuoles ?), two to four times as broad as the 

 separating bridges of protoplasm. Extracapsular body with dark pigment-powder of black or brown 

 colour, densely accumulated around the central capsule (in the matrix), loosely scattered between the 

 alveoles of the outer jelly-cover. The latter appears spotted by numerous large, roundish lumps of 

 protoplasm, scattered between the alveoles. No xanthellse. 



Dimensions. Diameter of the central capsule 0'3 to 0'6, of the nucleus 0'2 to 0'3, of the 

 hyaline globules in the protoplasm of the capsule 0'02 to 0'03 ; calymma, 2 to 3 mm. 



Habitat. South Pacific, Challenger Station 289. 



7. Tlialassicolla melacapsa, n. sp. (PI. 1, fig. 5). 



Spherical body in the central part opaque, black or dark coloured, in the periphery semi-trans- 

 parent, spotted. Central capsule compact, black, with a thick and firm, very elastic membrane, 

 areolated by polygonal, punctated figures resembling cells. Diameter of the central capsule about 

 twice that of the nucleus, one-third or half that of the jelly-cover. Nucleus thin-walled, trans- 

 parent, containing very numerous and small nucleoli. Protoplasm of the central capsule filled with 

 small black pigment-granules, quite intransparent, contains densely packed hyaline (albuminous ?) 

 globules of equal size ; every pellucid globule includes a smaller globule (one-third or one-fourth its 

 diameter), which appears to be composed of aggregated oil-bubbles. Extracapsular body without 

 pigment, contains between its alveoles in the inner half numerous, dark refractive oil-globules, in 

 the outer half numerous amceboid lumps of protoplasm, irregularly scattered. No xanthellse. 



Dimensions. Diameter of the central capsule 2 to 2 - 5, of the nucleus 1 to 1'5, of the hyaline 

 globules in the protoplasm of the capsule 0'03 to 0'04 ; calymma, 3 to 5 mm. 



Habitat. South-east Pacific (near Valparaiso), Challenger Station 300, surface. 



Genus 5. Thalassopliysa, 1 Haeckel, 1881, Prodromus, p. 470. 



Definition. Thalassicollida without intracapsular alveoles, but with large roundish 

 or globular alveoles within the extracapsular calymma. Nucleus in the centre of the 

 capsule papillate or branched. 



QKhaaaa., Quant,. 



