EEPOET ON THE RADIOLARTA. 839 



Genus 363. Lychnaspis,'^ Haeckel, 1862, Prodromus, p. 468. 



Definition. — D o ra t a sp id a with twenty palates, which are perforated by eighty 

 aspinal pores (four crossed pores in each phxte). Surface covered with numerous 

 hy-spines. 



The genus Lychnaspis, the hirgest and most common of all Dorataspida, exhibits 

 the same structure of the shell as its ancestral form Tessaraspis, and differs from it 

 only in the development of by-spines on the sutural condyles. Many species of this 

 genus are very widely distributed, and appear in large numbers, and some of them 

 are amongst the most graceful and elegant of the Eadiolaria. 



' Subgenus 1. Lychnasparium, Haeckel. 



Definition. — Condyles of the neighbouring plates connected by permanent open 

 sutures ; therefore the whole shell is composed of twenty separate pieces of acanthin. 



1. Lychnaspis giltscliii, n. sp. (PI. 95, fig. 3). 



Parmal meshes pentagonal, about ten or twelve times as broad as the thin bars, on an average 

 of the same size as the irregular polygonal sutural meshes. By-spines (two hundred to three 

 hundred) very delicate, half as long as the radius, Ijarbed, and zigzag. Eadial main-spines very 

 thin and long, straight, cylindrical ; their outer part longer than the inner part. 



Dimensions. — Diameter of the shell 0^2, of the parmal pores 0"02, sutural pores O^Ol to 0'03,, 

 bars 0-002. 



Habitat. — Tropical Atlantic, Stations 338 to 348, surface. 



2. Lychnaspis capiUaris, n. sji. 



Parmal meshes pentagonal, twenty to thirty times as broad as the very thin thread-like bars, 

 on an average of the same size as the irregular polygonal sutural meshes. By-spines (two hundred 

 to two hundred and fifty) very delicate, zigzag, with very small denticles, one-third as long as 

 the radius. Radial main-spines A'ery thin and long, cylindrical, more or less undulated. 



DiiiieTisions. — Diameter of the shell 0'25, parmal pores 0'025, sutural pores 0'02 to 01)4, bars 

 0-001. 



Habitat. — North Pacific, Station 250, surface. 



3. Lychnaspis maxima, n. sp. 



Parmal meshes pentagonal, six to eight times as broad as the thick bars, for the most part 

 larger than the irregular sutural meshes. By-spines (four hundred to five hundred) nearly as 



' ii/c/mciiipis = Lantern-shield ; 'hvxvo;, di-i;. 



