REPORT ON THE RADIOLARIA. 535 



9. Euchitonia virchowii, Haeckel. 



Euchitonia virchowii, Haeckel, 1862, Monogr. d. Radiol., p. 503, Taf. xxx. figs. 1-4. 

 Histiastrum fasciatum, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, 

 p. 842. 



Distance between the paired arms about half as large as their distance from the odd arm, which is 

 somewhat larger. Each arm with six broad chambers, bisected by a radial septum ; the terminal 

 chamber convex, blunt, twice as broad as the basal chamber. Patagium incomplete, with concave 

 chamber-rows, enveloping the arms with exception of the broad blunt terminal face. 



Dimensions. Eadius of the paired arms 015, of the odd arm 016 ; basal breadth - 05, terminal 

 breadth 01 to 012. 



Habitat. Mediterranean (Messina), Atlantic (Canary Islands). 



Subgenus 2. Pteractis, Ehrenberg, 1872 (loc. cit.). 

 Definition. Arms provided with radial spines at the distal end. 



10. Euchitonia elegans, Haeckel. 



Pteractis elegans, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 299, Taf. viii. 

 fig. 3. : 



Distance between the paired arms half as large as their distance from the odd arm. This latter 

 is straight, while both the former are concavely curved towards the middle line. Arms five times 

 as long as broad, at the distal end pointed and armed with a short conical terminal spine. 

 Patagium nearly complete, enveloping four-fifths of the arms, with four to five concave chamber- 

 rows. 



Dimensions. Eadius of the arms Q"2, breadth of them 0'03. 



Habitat. Tropical Pacific, Philippine Sea, depth 3300 fathoms (Ehrenberg). 



11. Euchitonia carcinus, n. sp. (PI. 43, fig. 10). 



Distance between the paired arms scarcely one-fourth as great as their distance from the odd 

 arm. This latter is straight, twice as long as the former, which are concavely curved towards the 

 middle line. The odd arm is three times as broad at the distal end as at the narrow base. The 

 end of each arm is furnished with a strong triangular radial spine and a group of smaller spines. 

 Patagium incomplete, with two to three concave chamber-rows, enveloping only the basal half of 

 the arms. 



Dimensions. Eadius of the paired arms 015, breadth 0'03; radius of the odd arm 0'3, breadth 

 on its base 0'02, on its distal end 0'07. 



Habitat. South Atlantic, Station 332, depth 2200 fathoms. 



