HEXACTINELLIDA. 3 
A curious phenomenon remains to be noticed. On October 24th, 1903, Lieutenant 
Armitage’s sledge party found a dried macerated Hexactinellid Sponge and also tufts of 
spicules being ‘“‘blown about by the wind amongst the erratics on the ice.” The 
existence of recent Hexactinellid Sponges on the surface of the earth and brought there 
by natural agencies is a very unusual occurrence ; for, generally, these Sponges live in 
too deep water to be cast up by storms. In the present instance, probably the sea 
bottom was scooped up by ice, and the material afterwards floated up on detached 
masses of ice. Both the specimen and tufts of spicules belong to a new species, viz., 
Aulorossella levis, common in shallow water up to 20 fathoms. 
ABBREVIATIONS AND EXPLANATIONS. 
(1) W.Q. means “ Winter Quarters.” 
(2) A Roman and an Arabic numeral in brackets mean number of plate and 
figure ; thus (I. 6) means Plate L, fig. 6. 
ORDER HEXACTINELLIDA, F. E. Scuvutze. 
Sup-orpER HexastreropHora, F. E. Schulze. 
Famity Rossevitipa, F. E. Schulze. 
Sup-FAMILY RossELtin.z, F. E. Schulze. 
Hyaxascus, Tjima. 
HYALAscus HODGSONI, 
(Plate III. fig. 1, and Plate IV. figs. 1 a-g.) 
Sponge an elongated, slightly flattened oval sac, broadest a little above the base, 
with an oval orifice with thin, soft, felt-like, unarmed edge. 
Surface with a few small, pointed, tuft-like conuli; with oxydiactin, and rarely 
oxypentactin pleuralia. With rounded base provided with short scattered bundles of 
basalia (probably forming a root-tuft in complete specimens). Gastral membrane 
continuous (to the naked eye). Autodermalia hexactins, rarely pentactins ; hypodermalia 
oxypentactins with smooth surface. Gastralia slender hexactins. Intermedia 
holoxyhexasters,* hemioxyhexasters, rarely monoxyhexasters * ; discohexasters, and 
microdiscohexasters. Colour (in spirit), pale buff; consistence rather soft and flexible, 
but firm enough for the walls to be self-supporting when out of spirit. 
Description of the specimen. The single specimen representing the new species 
appears to be in an incomplete state, and has probably been denuded of many pleuralia, 
* The term monoxyhexaster is used for oxyhexasters in which all the secondary or terminal rays are single, 
hemioxyhexasters (Ijima) being oxyhexasters in which only one, or some, but not all, of the terminal rays 
are single, and holoxyhexasters oxyhexasters with all the primary rays ending in more than one terminal ray ; 
similarly, the terms holodiscohexaster, hemidiscohexaster (Schulze), and monodiscohexaster explain themselves. 
Prof. Tjima’s view (4, p. 118, footnote) that the first kind of spicules, viz., monoxyhexasters, should be designated 
“‘hexasters” and not “hexactins” (Schulze, 9, pp. 8-11) seems to me justifiable. irstly, the axial canals are 
confined to the basal portion of each ray (primary ray) and do not extend to the terminal portion (secondary Tay). 
I have examined numerous monoxyhexasters and some monodiscohexasters, and by using a 12-inch oil immersion 
and by adjusting the light, I have invariably found that the axial canal comes to an abrupt end not far from the 
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VOL, III. 2H 
