THE TRUE FISHES. 



317 



coast, coming to the shores at the approach of warm weather. S 

 Goode : " The arrival of the menhaden is announced by their ai 

 the top of the water. They swim in immense schools, their b 

 the surface, packed side by side, and often tier above tier, aim 

 as sardines in a box. A gentle ripple indicates their position, and I 

 may be seen at a distance of nearly a mile by the lookoul a1 the masl 

 of a fishing-vessel, and is of great assistance to the seiners in setting 

 nets. At the slightest alarm the school sinks towards the bottom, 

 escaping its pursuers. Sailing over a body of menhaden swimming 

 short distance below the surface, one may see their glittering ba< 

 beneath, and the boat seems gliding over a floor inlaid with blocks 

 silver." 



The greatest use of menhaden is in the manufacture of c pogj oil.' 

 The fish are principally caught by seining, and then they are cooked in 

 salt water by means of steam, which separates a large part of tin- oil, 

 the rest being extracted by hydraulic pressure. The flesh and bones are 

 then made into artificial fertilizers to be used as manure. Some fish are 

 used as food, either fresh or pickled, while the young (shadines 

 packed in oil, and sold sometimes as sardines, sometimes as ' American 

 sardines.' 



The alewives are allied forms which ascend the rivers to lay their eggs. 

 and in some localities they have become ' land-locked ' ; that is, the} : 

 return to the sea. The shad is more important as a food fish, and is the 



largest of the herring-like forms. Some esteem it highly as a t 1 fish 



and indeed were it not for the seeming superabundance i i bones, it wou 

 rank among the best. The shad, too, go up the rivers to spawn. 

 gizzard-shad or mud-shad (Fig. 294) is a far less valuable form, which 1 

 become land-locked in various places. 



The true sardine is an European species, the fishery of which i> oi 

 importance. These fish are best broiled, but we are obliged to put 

 their bodies boiled in oil and packed in small tin boxes. The small sia 

 the bones, and the little lime which they obtain make it possible 

 sardines, bones, and all. 



At this point must be mentioned some deep-sea forms and so] 

 surface-swimming allies. In these, one of the most intei 

 the existence of luminous organs,— small spots whirl, give oft 

 spots are usually ranged along the sides of the body. Strangest oi 

 species "obtained at depths ranging between sixteen hundred and tw< 

 hundred and fifty fathoms, off the coast of Brazil, near Trig 

 and north of Celebes." The head is broad and flat, and tb 

 gone a most wonderful change; it occupies the whole upper su 



