the ' Challenger ' Monaxonida. 333 



Genus Gellius (Gray). 

 Very little horny matter, never forming distinct fibre. 



Gellius carduuSj n. sp. 



Sessile, oval, small. Greyish yellow. Texture loose but 

 firm ; interior cavernous. Surface with numerous angular 

 projections, many with oscula at summits. Dermal membrane 

 distinct. Large subdermal cavities. Skeleton : — (a) dermal, 

 a unispicular reticulation ; {h) main, loose, with no definite 

 fibres. Spicules blunted acerates, curved, rounded at each 

 end, size '6 by '023 millim. Bihamates of usual shape, size 

 •02 by -0012 millim. 



Localities. Station 148 a, Crozet Island, 240-550 fath. ; off 

 Prince Edward's Island, 85-150 fath. ; off Marion Island, 

 50-75 fath. ; Station 311, south-west coast of Patagonia, 245 

 fath. (var. magellanica) . 



Gellius Icevis, n. sp. 



Massive, sessile, large. Surface smooth ; oscula large and 

 even with surface ; spiculation as in G. cardum. 

 Locality. Station 320, off Kio de la Plata, 600 fath. 



Gellius glacialis^ n. sp. 



Massive, sessile, globular, lobate, or cylindrical ; size up to 

 3^ inches long by Ij broad. Colour pale greyish yellow. 

 Texture firm but very brittle. Surface even. Dermal layer 

 distinct, flaking off. Vents large, scattered, even with sur- 

 face. Skeleton arranged as usual. Spicules large stout 

 acerates, slightly curved, sharply and rather suddenly 

 pointed, size '65 by -036 millim. Bihamates large, of usual 

 shape, size up to "07 by '0063 millim. 



Localities. Station 142, Agulhas Bank, 150 fath. ; Station 

 145, Prince Edward's Island, 75 fath. (var. nivea). 



Gellius jlagellifer ^ n. sp. 



Massive, sessile. Diameter about 1 inch. Pale greyish 

 yellow. Soft and brittle. Surface even. Skeleton an irre- 

 gular reticulation of very loose spiculo-fibre. Spicules slightly 

 curved acerates, tapering to sharp points, size '42 by "018 

 millim. Bihamates very long, much curved, doubled on 

 themselves, size '06 by '0021 millim. (smaller ones also 

 present) . 



Locality. Off Marlon Island, 50-75 fath. 



