Long, from snout to end of tail, the exserted portion of the tusk may measure 6 or 7 and occasionally 8 ft.
It is often exserted with a rapid motion, sometimes with the object of feeling some object, sometimes under the influence of anger or fear.
The tongue is short, and the sheath in which it lies concealed opens near to the front margin of the lower jaw; scarcely more than the two terminating points are exserted from the mouth when the animal is in the water.
They are succeeded by succulent fruits, which are exserted, and frequently scaly or spiny, in which respects this genus differs both from Melocactus and Mammillaria, which have the fruits immersed and smooth.
The four succeeding sections, in which the ovipositor is modified into a sting (always exserted from the tip of the abdomen) and the trochanters are with few exceptions simple, form the Aculeata of Linnaeus.
E, Surface view of the shell with gill-tentacles exserted as in a, Mantle.
They are hypogynous, and have long and very delicate filaments, and large, linear or oblong two-celled anthers, dorsifixed and ultimately very versatile, deeply indented at each end, and commonly exserted and pendulous.
Some are enclosed within the tube of the flower, as in Cinchona (included); others are exserted, or extend beyond the flower, as in Littorella or Plantago.