. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. tentacles are ectodermal. The ectoderm of the aetinopharynx is higher than the and pigmented. The perfect pairs of mesenteries were prol)ably 6, as far I can see (in conformity with ). In a .section of about '/g of the middle part of the body 1 counted 3 perfect mesenteries and between those, one pair and a single mesentery, 1 pair of the second and 2 pairs of the third order. Of the latter one pair seems to be weaker than the other and prol>ably does not reach the
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. tentacles are ectodermal. The ectoderm of the aetinopharynx is higher than the and pigmented. The perfect pairs of mesenteries were prol)ably 6, as far I can see (in conformity with ). In a .section of about '/g of the middle part of the body 1 counted 3 perfect mesenteries and between those, one pair and a single mesentery, 1 pair of the second and 2 pairs of the third order. Of the latter one pair seems to be weaker than the other and prol>ably does not reach the Itodv-end. The tJ perfect pairs are provided with very strong, high and often kidney-shaped retractors, the folds of whicii are ratlier much branched (fig. 25). It is ])roi)able that also some of the mesenteries of the second order form distinct retractors although weaker than of the perfect pairs. In another sectioned part (see above), containing one |>air of directives, one pair of the second and two pairs of tiie third order, the one mesentery of the second cycle was provided with weak but distinct retractors of the same appearence as those of the first cycle. As also filaments and reproductive organs are present in the mesenteries of the first as well as of the second order, there is practically no distinct difference between mesenteries here. The muscles of mesen- teries of the third order are longitudinal and weak, the jiarieto- basilar and muscles weak. Daxielssex stated that the 6 perfect pairs of mesenteries were sterile. I cannot confirm this observation, the perfect mesenteries inclusive the directives were undoui)tedly ])rovided with testes, which, however, were little developed. At least certain mesenteries of the second order were also fertile. The specimen was apparently not full-grown. The nematocysts were usually not well preserved, only in the acontia thev were good. Especially it was difficult to distinguish Fig. 24. Sagarti
Size: 1249px × 2000px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
