244 INTRODUCTION TO ZOOLOGY. 



mentions the capture of one in the Esk, weighing 464 Ibs. 

 In the northern parts of Europe, where the fish is more abun- 

 dant, caviare is made of the roe of the female, and isinglass 

 from the dense membrane forming the air-bladder. 



OSSEOUS FISHES, 



WITH THE RAYS OF THE FINS FLEXIBLE. 



Our plenteous streams a various race supply, 



The bright-eyed Perch, with fins of Tyrian dye, 



The Silver Eel, in shining volumes roll'd, 



The Yellow Carp, in scales bedrop'd with gold, 



Swift Trouts, diversified with crimson stains, 



And Pikes, the tyrants of the watery plains." POPE. 



HAVING already noticed the Globe-fish (Fig. 179) and the 

 Trunk-fish (Fig. 180), which are members of a group con- 

 nected by some points of structure with the osseous,* and by 

 others with the cartilaginous fishes, we proceed to a small but 

 interesting order (Lophobranchii) in which the 

 gills are arranged like little tufts. To this be- 

 longs the Hippocampus or Sea-horse (Fig. 199), 

 and the Pipe-fishes (Syngnathidce), one of which 

 has been noticed in connexion with its powers of 

 movement (p. 222). This species is the largest 

 of our native Pipe-fishes (S. acus, Fig. 182), 

 and is furnished with a marsupial pouch. The 

 idea of such a pouch is connected with that of 

 i\\s female. We know that it is thus the female 

 Kangaroo carries and protects her young; but 

 in natural history we are for ever meeting such 

 strange occurrences, that it has been well said, 

 Fig. 199. " the naturalist has no need to invent ; Nature ro- 

 HIPPOCAMPUS. mancesitforhim." In the Pipe-fish, contrary to 

 what we find in other tribes of animals, the marsupial pouch 

 belongs to the male. The sexes come together in the month 

 of April ; the ova pass from the female, and are transferred 

 into the sub-caudal pouch of the male, the valves of the pouch 



* They belong to the Order Plectognathi, of Cuvier, characterised by 

 having the jaws as if soldered together. 



