EEPORT ON THE RADIOLARIA. 1155 



6. Peridium alatum, n. sp. (PI. 97, fig. 7). 



Shell subspherical smooth, with regular circular, hexagonaUy-framed pores. Basal plate with nine 

 pores (three larger central and six smaller distal pores). Horn apical, of equal size and the same form 

 as the three feet, three-sided prismatic, with three broad prominent wings, somewhat longer than the 

 sheU. 



Dimensions. — SheU 0'07 long, O'OS broad ; horn and feet 01 to 012 long. 



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



7. Peridium cervinum, n. sp. 



Shell subspherical, spiny, with subregular circular pores. Basal plate with four pores (?). 

 Horn apical, conical, about as long as the shell. Feet three to four times as long, cylindrical 

 curved, with irregular simple or forked branches like the antlers of a deer. 



Dimensions. — Shell diameter 01, horn 01 long, feet 0'3 to O'l long. 



Habitat.- — Central Pacific, Station 266, depth 2750 fathoms. 



Genus 509. Archipera,^ Haeckel, 1881, Prodromus, p. 429. 



Definition. — A rchiperida (vel Monoeyrtida triradiata clausa) without internal 

 columella, with two or more apical horns. 



The genus Archipera differs from the preceding Peridium only in the multiplication 

 of the apical horn, which in the latter is always simple. The number of horns is 

 usually two or three, sometimes four or more. The species bearing three horns may be 

 derived directly from Triceraspyris by loss of the sagittal ring. 



1. Archipera cortiniscus, n. sp. (PI. 98, fig. 5). 



Shell ovate, thorny, with large roundish pores, which are closed by sieve-plates with numerous 

 small porules. Basal plate with two pairs of simple large pores (two smaller jugular and two 

 larger cardinal, similar to PL 98, fig. lOi). Two horns divergent, curved, slender, pyramidal ; the 

 apical horn longer than the shell, the frontal horn shorter. Three feet divergent, longer than the 

 shell, three-sided prismatic, at the distal end club-shaped, thorny. 



Dimensions. — Shell 01 long, O'OS broad ; horns and feet Oil to 014 long. 



Habitat. — Tropical Pacific, Station 225, depth 4475 fathoms. 



2. Archipera pentacantha, n. sp. 



Shell pear-shaped, smooth, with numerous and small irregular roundish pores. Basal plate with 

 three larger pores. Two horns and three feet of nearly equal size and similar form, three-sided 



