THE MEDUSAE OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 173 



Genus Halicreas, Fewkes, 1882. 



Generic Character (MAAS, 1 905). Trachomedusse with very numerous tentacles 

 (more than fifteen in an octant), which by their unequal sizes show different times of 

 appearing ; with a long tubular mouth ; with eight perradial outgrowths of jelly near 

 the margin of the umbrella. 



Halicreas papillosum, Vanhoffen, var. antarcticum, nov. 



Halicreas papillosum, Vanhoffen, 1902, p. 68, Taf. is. fig. 7-8, Taf. xi. fig. 30; 

 Maas, 1905, p. 57, Taf. x. fig. 70, Taf. xi. fi. 71. 



Station 413, lat. 72 02' S., long. 23 40' W. Vertical net, 0-1000 fathoms. 

 15th March 1904. 



Two specimens belonging to the genus Halicreas were taken at this station, and 

 both are unfortunately in very bad condition. 



Specimen No. 1. The umbrella is about 30 mm. in diameter, and is quite flattened 

 out. On the ex-umbrella, at a short distance above the margin, there are eight clusters 

 of papillate processes in the radii of the radial canals. In shape and size these clusters 

 resemble the papillate processes of Halicreas papillosum (Vanhoffen, 1902, Taf. ix. 

 fig. 7-8). There are, however, one or two isolated processes in most of the radii, just 

 above the principal cluster. 



The stomach has been completely torn out, and not even a trace of it remains. The 

 radial canals have nearly all shared the fate of the stomach, but two have been fairly 

 well preserved from destruction, and are very broad. There are indications of six 

 more canals. 



Only the lower parts of the gonads remain on four of the radial canals. The gonads 

 lie in groove-like depressions of the sub- umbrella, and do not extend to the margin of 

 the umbrella. The radial canals and gonads are whitish in formalin. On the surface 

 of the sub-umbrella, somewhere about the periphery of the stomach, there are eight 

 semi-globular projecting lumps of jelly, one between every two radial canals. 



The margin of the umbrella is in bad condition, and only the basal stumps of the 

 tentacles, partly embedded in the margin of the umbrella, now remain. The stumps 

 show that the tentacles are very numerous. 



Specimen No. 2. This specimen is much smaller than the one described above, and 

 looks like a contorted mass of jelly. It shows the eight' clusters of papillate processes 

 near the margin of the umbrella, and the eight semi-globular projections on the sub- 

 umbrella. It is, however, an important specimen, because it shows that the top of the 

 umbrella is capped by a small, low, somewhat spherical lump of jelly, which is studded 

 with about nine small, somewhat conical processes, or tubercles. They closely resemble 

 the marginal processes in shape and size, but are more isolated, being spread over a 

 larger area. In the largest specimen a rather oval cap with about three or more 



(ROY. soc. EDIN. TRANS., VOL. XLVI., 237.) 



