REPORT ON THE DEEP-SEA MEDUSAE. 85 



uanie of Periphema regina, as I had already done in the Prodronius (1877). Whilst in 

 the true Periphylla (P. mirabilis, P. hyacinthina, &c.) the four large interradial 

 conical funnel cavities of the subumbrella traverse the whole length of the central 

 and basal stomach, and meet with their points in the centre of the umbrella cone, 

 in Periphema regina they stop short a little way below the subumbrella, so that the 

 four points of the conical funnel cavities remain separated by a basal hollow space, which 

 has the geometrical basis of a quadrate pyramid, and fills the point of the cone. The four 

 perradial niches of the basal stomach are consecpaently connected at their aboral ends 

 by this conical cavity, whilst they are completely separated in the true Periphylla. 



Periphema regina, Hseckel (Pis. XXIV., XXV.). 



Periphema regina, Hreckel, 1877, Prodrom. System. Medus., No. 389. 

 Periphylla regina, Hfeckel, 1879, System der Medusen, p. 421, No. 423. 



Umbrella bell-shaped, nearly as high as broad. Pedal zone of the exumbrella rather 

 narrower than the lobe zone, both together nearly as high as the cone zone. Marginal lobes, 

 oval, rounded obtusely, their distal wings nearly semicircular, about half as high as their 

 proximal gelatinous swelling. The eight tentacle lobes project further on the umbrella 

 margin than the eight rhopalia lobes. Tentacles very thick, nearly as long as the height 

 of the umbrella, one-third as broad at their base as the marginal lobes. (Esophagus 

 cubical, very large and very thick-walled, nearly half as high and half as broad as the 

 umbrella, the oral margin in the plane of the umbrella margin, without barbous filaments. 

 Horizontal diameter, 180-200 mm. ; vertical diameter, 180-200 mm. 



Habitat. — The Antarctic Ocean, south-west of the Kerguelen Islands. Lat. 62° 26' S., 

 long. 95° 44' E. Station 156. The large specimen, to which the fragments examined 

 belonged, was a mature female, and was taken from a depth of 1975 fathoms, 26th 

 February 1874. The colour of the broken fragments, otherwise well preserved in 

 spirit, was reddish, the ovaries were brownish-yellow and the endodermal epithelium 

 of the abaxial wall of the coronal sinus — or the inner surface of gelatinous umbrella — 

 from dark red-brown to black-brown. 



The umbrella (PL XXIV. figs. 1, 2) of Periphema regina, as far as could be made 

 out from the fragments to hand, is bell-shaped, considerably more depressed than in 

 Periphylla mirabilis. Its apex is flatly truncated, and nearly ecpial in height to the 

 diameter of the bell opening, 18-20 cm. The exumbrella is divided by a broad, deep 

 coronal furrow (fig. 2, ec), nearly in the middle of the height, into an upper umbrella 

 cone, and a lower umbrella corona. The umbrella cone is smooth, flattened above, and 

 almost hemispheroidal. The coronal furrow is very broad, and the gelatinous substance 

 of it very much thinned. It is divided by sixteen subradial longitudinal furrows (which 

 pass below into the lobe clasps) into sixteen broad, crescentic arese ("areola) semilunares," 

 fig. 2, ec). A vane-like-shaped process of the exumbral zonal muscle (mz) lies between 



