OCR Text |
Show 1903.] MEDUSAE FROM BRITISH COLUMBIA AND ALASKA. 179 separation is justifiable, seeing that Brandt seems to have misunderstood the structure of his species. We should hesitate, therefore, to base any distinctions on his account. III. EucoriDiE Gegenbairr. PHIALIDIUM Leuckart. 1. PHIALIDIUM LANGUIDUM Haeckel (18, p. 185). Synonym Oceania languida A. Agassiz. Specific description.-The bell is hemispherical, about 12 mm. in diameter by 6 mm. high. It is folded in the peculiar manner described by Agassiz (2). The velum is narrow and delicate. The tentacles all told number sixty, some closely coiled, others straight. The tentacle-bulbs are somewhat smaller here than in P. gregaria, the tentacles being sharply set off from the bulbs. There are two otocysts between each two tentacles. The stomach is small and cross-shaped, the arms of the cross receiving the radial canals. There is no proboscis. The curled and fringed oral lobes are about the same length as the arms of the stomach cross. The four radial canals bear the gonads on their distal half. They are oblong linear bodies, one-third the length of the radial canals, attached to their outer half, but not reaching quite to the circular canal of the bell-margin. Colour.-Greenish blue. Habitat.-Victoria Harbour, collected by Shearer. 2. PHIALIDIUM GREGARIUM Haeckel (18, p. 188). (Plate XX. figs. 1 & 1 a.) Synonym Oceania gregaria A. Agassiz. Specific description.-The bell is 12 mm. by 7 mm., and so nearly hemispherical. The velum is quite small. Of the tentacles and buds destined to develop there are sixty. The tentacle-bull s are spherical and relatively large. The otocysts are evenly distributed, one or two between consecutive tentacles ; they usually contain one, sometimes two otoliths. The stomach is very small, quadrangular, receiving the delicate radial canals at its angles, and ending in the four perradial, moderately long, curled, and fringed oral lobes. There is no proboscis. The four radial canals run from the angles of the stomach to the circular canal, bearing on their distal half or third the gonads, which, however, do not reach quite to the circular canal. As the gonads are very narrow linear bodies, our specimens may be immature. This is borne out by the size and number of small tentacles. Colour.-White, becoming slightly brown on preservation in formalin. 12* |