The Cambridge natural history . t vessels, with which the upper part of the pulmonarychamljer is furnished, can Ijc clearly seen by looking through theaperture as it dilates. It is only in the Auriculidae that anactual spongy mass of lung material appears to exist. When inmotion, a Helix inspires air much more frequently than whenat rest. Temperature, too, seems to affect the niunber of inspira-tions ; it appears doubtful whether, during hibernation, a snail BREATHING ORGANS IN PULMONATA i6i breathes at all. In any case, the amount of air required tosustain life must be small. With regard to t
The Cambridge natural history . t vessels, with which the upper part of the pulmonarychamljer is furnished, can Ijc clearly seen by looking through theaperture as it dilates. It is only in the Auriculidae that anactual spongy mass of lung material appears to exist. When inmotion, a Helix inspires air much more frequently than whenat rest. Temperature, too, seems to affect the niunber of inspira-tions ; it appears doubtful whether, during hibernation, a snail BREATHING ORGANS IN PULMONATA i6i breathes at all. In any case, the amount of air required tosustain life must be small. With regard to the respiration of fresh-water Pulmonata thereappears to be some difference of opinion. It is held, on the onehand, that the Limnaeidae only respire air, making periodic visitsto the surface to procm-e it, and that they perish, if preventedfrom doing so, by asphyxiation. If, we are told,^ as a Limnaeais floating on the surface of the water in a glass jar, a morsel ofcommon salt be dropped upon its outstretched foot, it will sink.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
