1178 THE VOYAGE OF H.M.S. CHALLENGER. 



Subgenus 1. Coronoplcena, Haeckel, 1881, Prodromus, p. 429. 

 Definition. — Feet simple, not branched nor forked. 



1. Archijjhcena gorgospyris, n. sp. (PI. 98, figs. 10, 10a). 



Shell hemispherical, smooth, with small subregular, circular pores. Collar septum with four 

 large jDores (fig. 10a). Twelve to fifteen feet, divergent, lamellar, truncate, about as long as the shell. 

 (Similar to certain forms of Gorgospyris, PI. 87, figs. 1 to 3, but with simple shell cavity, without 

 sagittal ring and constriction, and without a columella.) 



Dimensions. — Shell 0-08 long, 0-04 broad ; feet O'OS to 0-04 long. 



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



2. ArchiphcBna corona, n. sp. 



Shell crown-shaped, somewhat broader than long, at the base flattened, papillate, with irregular 

 roundish pores. Twenty to twenty-five feet, broad, lamellar, truncate, nearly vertical, about twice as 

 long as the shell. 



Dimensions. — Shell O'l long, 0'12 broad; feet 0'2 to 0'22 long. 



Habitat. — Central Pacific, Station 268, depth 2900 fathoms. 



Subgenus 2. Stephanop>h(ena, Haeckel, 1881, Prodromus, p. 429. 

 Definition. — Feet liranched or forked. 



3. ArcMplicBna stephanoma, n. sp. 



Shell campanulate, somewhat longer than broad, with subregular, circular pores. Margin of the 

 flattened base with a corona of about twenty unequal feet, which are partly simple, partly irregularly 

 branched, and about as long as the shell. 



Dimensions. — Shell Oil long, 0'03 broad; feet 0'08 to 0'12 long. 



Habitat. — Central Pacific, Station 271, depth 2425 fathoms. 



Family LXI. C yrtoc alpid A, n. fam. 



Archicorida et Archicapsida, Haeckel, 1881, Prodromus, pp. 427, 428. 



Definition. — M onocyrtida eradiata. (Cyrtoidea with a simple, not jointed 

 shell, representing a simple cephalis without radial apophyses.) 



The family Cyrtocalpida, composed of the Archicorida and Archicapsida of my 



