TELEOSTEI. 361 



they are seen swimming along the surface of the water, striving 

 cunningly to glide under the bellies of the horses. By the 

 force of their invisible blows numbers of the poor animals are 

 suddenly prostrated ; others, snorting and panting, their manes 

 erect, their eyes wildly flashing terror, rush madly from the 

 raging storm ; but the Indians, armed with long bamboo staves, 

 drive them back into the midst of the pool. 



" By degrees the fury of this unequal contest begins to 

 slacken. Like clouds which have discharged their electricity, 

 the wearied eels disperse. They require long rest and nourish- 

 ing food, to repair the galvanic force which they have so 

 lavishly expended. Their shocks gradually become weaker 

 and weaker. Terrified by the noise of the trampling horses, 

 they timidly approach the banks of the morass, where they are 

 wounded by harpoons, and drawn on shore by non-conducting 

 pieces of dry wood. 



" Such is the remarkable contest between horses and fish. 

 That which constitutes the invisible but living weapon of these 

 inhabitants of the waters that which, awakened by the con- 

 tact of moist and dissimilar particles, circulates through all the 

 organs of animals and plants that which, flashing amid the 

 roar of thunder, illuminates the wide canopy of heaven which 

 binds iron to iron, and directs the silent recurring course of 

 the magnetic needle all, like the refracted rays of light, flow 

 from one common source, and all blend together into one 

 eternal all-pervading power." 



The second group of the Malacopteri is that of the Abdomi- 

 nalia, in which there are ventral fins, and these are abdominal 

 in position. Space will not permit of more here than merely 

 mentioning that in this section are contained amongst others 

 the well-known and important groups of the Clupeidce (Herring 

 tribe), the Pikes (Esotida), the Carps (Cyprinidce), the" Sternop- 

 tixince, and the Salmonidce, comprising the various species of 

 Salmon and Trout. Also belonging to this group are the 

 Sheat-fishes (Siluridce), which are chiefly noticeable because 

 they are amongst the small number of living fishes possessed 

 of structures of the same nature as the fossil spines known as 

 " ichthyodorulites." The structure in question consists of the 

 first ray of the pectoral fins, which is largely developed and 

 constitutes a formidable spine, which the animal can erect and 

 depress at pleasure. Unlike the old "ichthyodorulites," how- 

 ever, the spines of the Siluridcz have their bases modified for 

 articulation with another bone, and they are not simply hollow 

 and implanted in the flesh. The " Siluroids " are also remark- 

 able for their resemblance to certain of the extinct Ganoid 



