Medusae of the world . widest at its middle and is spindle-shaped inoutline, being quite narrow where it arises from the stomach and also at its distal end. Thepouches are not cleft at their distal ends by the insertions of the tentacles, for the roots of thetentacles lie above them as in other species of Cunoctantha. The most remarkable characteristic of this medusa is the presence of medusa-buds invarious stages of development upon the 8 peripheral stomach-pouches. These buds are notparasites, but are formed from both ectoderm and entoderm of the stomach-pouches and NARCOMEDUSJE—CUNOCTANTHA,
Medusae of the world . widest at its middle and is spindle-shaped inoutline, being quite narrow where it arises from the stomach and also at its distal end. Thepouches are not cleft at their distal ends by the insertions of the tentacles, for the roots of thetentacles lie above them as in other species of Cunoctantha. The most remarkable characteristic of this medusa is the presence of medusa-buds invarious stages of development upon the 8 peripheral stomach-pouches. These buds are notparasites, but are formed from both ectoderm and entoderm of the stomach-pouches and NARCOMEDUSJE—CUNOCTANTHA, ^EGJNURA. 467 project outward into the bell-cavity. The mouth-tube develops before the lappets and ten-tacles. The oldest bud had 8 tentacles, 8 lappets, and 16 sense-organs (2 on each marginallappet). The sperm or ova were not developed in the single specimen studied by Browne, and as hestates the medusa is probably in an intermediate stage preceding sexual maturity, during whichtime it produces medusae Fig. 306.—Cunoctantha fowleri, after Browne, in Trans. Linnean Soc. London. Found in the Bay of Biscay between 50 fathoms and the surface. It is the only Cunoctantha or Cunina known to produce medusa-buds as external out-growths of its body-wall. Cunoctantha tenella Bigelow. Cunoctantha tenella, Bigelow, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 54, plates 15-17. Bell 7 mm. and more in diameter, higher than a hemisphere, exumbrella smooth. Lappetzone narrow but slightly incised in the tentacular radii. Peronial strands very short. 8 taperingtentacles, as long as bell-radius. At least 3 sense-clubs per lappet as in C. octonana but theotoporps are less prominent. Stomach deep and lenticular with a round nearly triangular, pointed, gastric pouches. A well-developed peripheral, peronial canal-system is present, this being the only known form of Cunoctantha known with certainty tohave marginal canals. Colorless. Gonads begi
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectcnidari, bookyear1910
