REPORT ON THE RADIOLARIA. 1235 



Genus 552. Micromelissa,^ Haeckel, 1881, Prodromus, p. 433. 



Definition. — S ethoperida (vel Dicyrtida triradiata clausa), wdth three divergent, 

 solid, lateral wings. Ceplialis with a horn. 



The genus Micromelissa diflers from the two preceding genera in the free pro- 

 minence of the three cortinar ribs, forming three solid lateral wings. Beyond these 

 the thorax walls are convergent, and the basal mouth closed by a lattice-plate. 

 Therefore Micromelissa may have arisen from Lithomelissa simply b)' development of 

 this basal mouth-plate. 



1. Micromelissa bo^nbus n. sp. (PI. 57, fig. 14). 



Shell smooth, with sharp collar stricture. Length of the two joiuts =1:4, breadth = 1:5. 

 Cephalis spherical, with an oblique conical horn of the same length. Thorax subspherical, in the 

 upper half with three conical, downwardly diverging wings, about as long as its radius. Pores very 

 small and scarce. 



Bivunsions. — Cephalis 0"02 long, 002 broad ; thorax 0'09 long, 0"1 broad. 



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



2. Micromelissa vespa, n. sp. 



Shell smooth, with deep collar stricture. Length of the two joints = 2:5, breadth = 2:3. 

 Cephalis spherical, with an oblique pyramidal horn twice the length. Thorax inversely ovate, 

 in the upper half with three pyramidal wings, which are equal to its breadth, little curved and 

 diverging downwards. Pores very small and scarce. 



Dimensions. — Cephalis 0'04 diameter ; thorax Ol long, 0'06 broad. 



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



3. Micromelissa apis, n. sp. 



Shell rough, with deep coUar stricture. Length of the two joints = 2:3, breadth = 2:4. 

 Cephalis subspherical, with a straight conical horn of half the length, and subregular, circular, double- 

 contoured pores, of the same breadth as the bars. Thorax Uttle larger, subspheiical, with irregular, 

 roundish pores, twice to four times as broad as the bars. From its lower half arise three short 

 conical wings, curved downwards, and half as long as the cephahs. 



Dimensions. — Cephahs 0'04 long, 0'04 broad ; thorax O'QG long, 0'08 broad. 



Habitat. — South Pacific, Station 295, depth 1500 fathoms. 



' Micromelissa = Small bee ; /aix^o;, fttT^iaax. 



