SCYPHOMEDUSAE 355 



irregular large warts on the central disc and the lappets (St. 8). In most cases the apex 

 of the umbrella is evenly rounded, but some specimens show at the spot on the apex 

 where the opening of the so-called " Stielcanal " might be expected, a more or less deep 

 crater-like groove, which seems to be a healed cicatrice (Sts. 72, 85, 151). In others 

 there is a deep hole at the apex (Sts. 72, 391, 395, 414: Plate XIV, figs, i and 2) (see 

 P- 356). 



The LAPPETS (Plate XIV, figs, i, 2) are oval, broad and spade-shaped, the tentacular 

 ones being a little longer and broader than the rhopalar ones. The latter often include 

 a broader angle and their outline is a little more curved inwards. The strongly developed 

 white or reddish lappet muscles are often visible through the more or less transparent 

 lappets, so that the latter are no longer entirely transparent. 



The TENTACLES are thick, especially thickened on the base, often broad and ribbon 

 like, in the largest specimen 250 mm. long. 



The PEDALiA (Plate XIV, figs. 1,2; XV, fig. 3) in the present large specimens of the 

 regina type are broad and blunt, only a little vaulted, rather oblong or rectangular, and 

 never globular or semiglobular. Rhopalar and tentacular pedalia are of a difl^erent form. 

 The clefts on both sides of the tentacular pedalia run straight, but those on both sides 

 of the rhopalar ones run more irregularly, proximally curved outwards, distally more 

 inwards, S-shaped, and forming an angle on both sides of the rhopahum (see Plate XIV, 

 fig. 2, middle), so that the rhopalar pedalia seem to be constricted and pointed, the 

 tentacular ones being rectangular and transversely cut oiT. The clefts in the large 

 specimens never originate from the lower border of the annular furrow, but begin at a 

 distance of about 10-12 mm. from it. Between the coronal furrow and the origin of the 

 clefts there is a broad, even, flat zone which separates the pedalia from the furrow. This 

 is very typical for all specimens of the present series and the shape of the pedalia is thus 

 quite difl^erent from all figures in the literature of large dodecabostrycha or regina. In 

 hyacinthina the clefts between the pedalia extend from the lower border of the coronal 

 furrow and divide the latter into numerous small flexures which together form a wavy 

 line. In the present specimens it runs straight and is not wavy at all. The rhopalar 

 pedalia are always a little narrower than the tentacular ones but the diff'erence in size 

 of both is never as large as in a Discovery specimen mentioned by Browne (1910, p. 46), 

 for it is 10 mm. in this specimen. 



The STOMACH of the specimens of the regina type is very thick-walled and much 

 stronger than in the specimens of forma hyacinthina . In not a single specimen was the 

 apex evenly rounded, and in one or two cases only (Sts. 239, 366) a thin apical pro- 

 jection into the mesogloea was to be seen (the so-called " Stielcanal"). In most speci- 

 mens the stomach is highly vaulted, rising to the apex in the form of a sort of tent, which 

 is suspended on the four septa. On both sides of these there are often to be seen four 

 pairs of pouches, which give to the stomach, if seen from above, the outline of an eight- 

 rayed star — a very obvious feature (Plate XIV, fig. i ; XV, fig. 3). In several specimens 

 a round deep gap in the mesogloea at the apex is to be seen (e.g. Sts. 72 and 395), which 



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