REPORT ON THE RADIOLARIA. 1285 



partly interrupted, longitudinal rows, separated by prominent crests. Mouth little constricted. 

 Peristome with twenty to twenty-four broad, lamellar, pointed feet, which are about as long as the 

 shell, little curved, and convergent. 



Dimensions. Cephalis O'Ol long, 0'04 broad ; thorax 0'09 long, 0'09 broad. 



Habitat. North Pacific, Station 244, depth 2900 fathoms. 



21. Carpocanium virgineum, n. sp. (PL 52, fig. 20). 



Shell ovate, smooth, with flat, perfectly hidden cephalis. Length of the two joints = 1:8, breadth 

 = 3:9. Pores regular, circular, hexagonally framed, as broad as the bars, in about sixteen longi- 

 tudinal rows on each side. Mouth little constricted. Peristome with eighteen to twenty -four very 

 large, lamellar, pointed feet, which are longer than the shell, and so curved and convergent that 

 their distal points come nearly in contact. 



Dimensions. Cephalis O'Ol long, 0'03 broad ; thorax 0'08 long, 0'09 broad. 



Habitat. Central Pacific, Station 272, depth 2600 fathoms. 



Subfamily 2. SETHOPH^NIDA, Haeckel, 1881, Prodromus, p. 433. 



Definition. A nthocyrtida with the basal mouth of the shell fenestrated 

 (vel Dicyrtida multiradiata clausa). 



Genus 570. Sethophcena, 1 Haeckel, 1881, Prodromus, p. 433. 



Definition. S ethophsenida (vel Dicyrtida multiradiata clausa) with lateral 

 apophyses. Cephalis with a horn. 



The genus Sethophcena aud the following Clistophcena form together the small sub- 

 family of Sethophsenida, comprising those Dicyrtida in which the thorax bears numerous 

 radial appendages (four to six or more), and the mouth is closed by a lattice-plate. In 

 Sethophcena the apophyses are lateral wings, as in Micromelissa, from which it may be 

 derived by development of secondary wings, interpolated between the three primary 

 wings. 



1. Sethophcena tetraptera, n. sp. 



Shell smooth, with deep collar stricture. Length of the two joints = 3:10, breadth = 

 4 : 9. Cephalis subspherical, without horn. Thorax ovate, with rounded hemispherical base, and 

 subregular, hexagonal pores. From its upper half (below the collar stricture) arise four divergent, 



1 Sethophoena= Sieve-shell ; oi$a, (pair*. 



