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111.
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SYNOPSIS. Supraspecific taxa of the ciliate Order Tintinnida Corliss, 1955 are indexed by 304 entries; genetic type species are cited with reference to the original citation. The accompanying bibliography of 133 entries includes those publications cited in the index. Authors for several type citations are corrected, as is authorship of some genera, and a new type designation is made for Parundella to replace the previous erroneous designation. Genera present in the fossil record are so indicated. 相似文献
113.
Daily studies were made of the osmoregulatory abilities of Cardisomaguanhumi from hatching to the end of larval development. Theseresults were compared to those of similar research on osmoregulationby larvae and megalopa of four species of estuarine, littoral,and sub-littoral crabs. The comparison shows that larvae ofC. guanhumi possess the same kinds of adaptations for waterintake at the time of molt that were found in Rhithropanopeusharrisii. Land-crab larvae hyperregulated in 10 p.p.t. sea waterand hyporegulated in water of 40 p.p.t. for experimental periodsfor 2 hr during the first one-third of their development. Duringthe remainder of larval life, they hyporegulated against 15p.p.t. in intermolt periods and became isosmotic with, or hyporegulatedagainst, 10 p.p.t. at the time of molting. From the time ofhatching, the osmoregulatory pattern of developing C. guanhumifits them for deep penetration of estuaries and for crossingsteep saline gradients. This pattern is evidence for a strongerand more enduring control of water balance, especially at thetime of molting, than we have found in non-terrestrial species. 相似文献
114.
Larvae of the land-crab, Cardisoma guanhumi, Latreille. weremaintained in 24 different combinations of salinity and temperaturefrom the time of hatching. Survival to the first crab occurredin salinities of 1545 p.p.t., 25° and 30°C. Durationof the five zoeal and one megalops stages was similar in salinitiesof 2040 p.p.t., but at 15 and 45 p.p.t. a greater periodof time was required for total development. Mortality of allthe larvae at 20°C suggests that temperature plays a moreimportant role in survival and distribution of the larvae ofC. guanhumi than salinity. Increments of size in crabs during the first seven post-larvalmolts were similar in salinities of 535 p.p.t., 25°C,but in fresh water increase in size at the time of molting wasreduced. Although there was no apparent relationship betweenfrequency of molting and salinities of 535 p.p.t., theduration of intermolt was reduced in crabs maintained in freshwater, and survival was also lower. From the present study there is no indication that the morphologicaland physiological processes that are associated with adaptationof the adult crab to the terrestrial environment are initiatedduring larval development. Although the adult crabs have successfullypenetrated the terrestrial environment, the pelagic larvae arestill subject to the numerous ecological variables of the estuarineand marine environments. 相似文献
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