EEPORT ON THE RADIOLARIA. 1465 



Genus 641. Sticliophcena,^ Haeckel, 1881, Prodromus, p. 439. 



Definition. — Stic h ophsenid a (vel Stichocyrtida multiradiata clausa) with nine 

 radial ribs or wings. 



The genus Stichophmia differs from the preceding Artopli(ena in the typical number 

 of the radial lateral appendages, being nine in the former, six in the latter. Usually these 

 are simple ribs enclosed in the sheU-wall, more rarely prominent wings. 



Subgenus 1. Stichophcenidium, Haeckel. 

 Definition. — Last joint of the shell rounded, without basal spines. 



1. Stichop>hcBna ritteriana, n. sp. (PI. 75, fig- 12). 



Shell pear-shaped, twice as long as broad, with seven internal annular septa. Tlie upper half is 

 slenderly conical, composed of seven joints of nearly equal length, gradually increasing in breadth. 

 The lower half is formed only by the eighth joint, which is very large, subglobose, inflated, and as 

 long as the seven other joints together. The spherical cephaHs bears a conical horn of the same 

 length. From the thorax arise at equal distances nine radial ribs in the form of thin, triangular 

 lamellae, which attain their greatest height in the sixth joint, and form nine elegant, denticulate 

 crests in the eighth joint. Pores small and numerous, subregular, circular. This beautiful species 

 is dedicated to my honourable friend, Dr. Paul von Eitter, the magnanimous philanthropist and 

 liberal protector of free science, who founded in the University of Jena the first professorial chair 

 of Darwinism and phylogeny. 



Dimensions. — Length of the shell (with eight joints) 0'24, breadth 0'12. Length of each of the 

 first seven jomts 0"015 ; diameter of the subspherical last joint 0"12. 



Habitat. — South Pacific, Station 300 (ofT Juan Fernandez), depth 1375 fathoms. 



2. StichophoBna darwiniana, n. sp. 



Shell pear-shaped, twice as long as broad, with six distinct strictures. The last joint is the 

 broadest and twice as long as the sixth, three times as long as each of the five preceding joints. 

 The hemispherical cephalis bears a conical horn of twice the length. From the third joint arise 

 nine radial ribs, which reach the sixth joint, but are not developed in the last hemispherical joint. 

 Pores irregular, roundish. 



Dimensions. — Length of the shell (with seven joints) 0"2, breadth 0"1. Length of five first 

 joints, each 0-018 to 0-022, of the sixth 0-03, of the seventh joint 0-06. 

 Halitat. — Central Pacific, Station 265, depth 2900 fathoms. 



1 Stichophcsna = Row-shell ; inix<"^, (pahix. 

 (ZOOL. CHALL. EXP. — PAKT XL. — 1886.) Er 184 



