and by means of this apparatus they give violent shocks to animals with which they come in contact.
Hardly less strange than the rays are those animal structures
![](http://upload.wikimedia.org/wikipedia/commons/thumb/0/04/PSM_V11_D545_Torpedo_fish.jpg/300px-PSM_V11_D545_Torpedo_fish.jpg)
Fig. 4. Torpedo. b, brain; eo, eye and optic nerve; el, electric organs; sn, spinal nerves; sm, spinal marrow; pg, pneumogastric nerves going to the electric organs; pg’, branch of the preceding; g, gills.
which remind us somewhat of the rays on the one hand, and the sharks on the other, but which differ from both in several important respects, but especially in having a very long depressed and bony
![](http://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/PSM_V11_D545_Mackerel_shark.jpg/300px-PSM_V11_D545_Mackerel_shark.jpg)
Fig. 5. Mackerel-Shark (Lamna punctata, Storer).
snout, armed on each side with spines implanted like teeth, the whole constituting a most formidable weapon. These are the sawfishes (Fig. 7), which attain a length of fifteen feet or more.