678 NATURAL HISTORY OF AQUATIC ANIMALS. 



species of fish in Massachusetts Bay, such as cod, haddock, and mackerel. They cling to the side 

 of the fish beneath the pectoral, and suck its blood until the flesh becomes as white as paper. 



There can be but little doubt that to the Lampreys may be credited an immense destruction 

 of the various food -fishes which enter estuaries and rivers. It is by no means uncommon for 

 fishermen to find them attached to halibut and other large species caught at sea. Lampreys are 

 found far inland, ascending most of the creeks and rivers of Central Europe and of temperate 

 North America far toward their sources. In fact the distances from the sea at which the so-called 

 "sea Lamprey "of Europe is constantly found are so great, when their feeble powers of loco- 

 motion are considered, that Dr. Giinther in his essay on the fishes of the Neckar was induced to 

 advance the theory that they are carried from the sea to the river sources by the shad, salmon, 

 and other fish to which the Lampreys attach themselves. This view is combated by Blan- 

 ehard, who claims that no one has ever seen Lampreys attached to salmon. If I am correctly 

 informed, salmon are largely annoyed by Lampreys in the United States, but it seems hardly 

 necessary at present to accept Giinther's theory in the fullest extent, since the Lamprey is appar- 

 ently not much inferior to the eel in powers of locomotion, and the eel, it is well known, accom- 

 plishes long migrations without apparent inconvenience. 



It has been customary among writers upon fishes to class the Lampreys among the migratory 

 fishes, and to describe the migrations of the sea Lamprey as beginning in the spring, when they 

 are supposed to ascend the rivers for the purpose of spawning in their headwaters. This theory 

 seems at present hardly tenable; so little, however, is known of their habits that the theory cannot 

 be pronounced absolutely incorrect. There are, however, certain species of Lampreys in Europe 

 which are believed to live entirely in fresh water. A similar statement can most positively be 

 made regarding our species inhabiting the Great Lakes and other inland waters of North America. 

 On the other hand, many of the sea Lampreys remain in salt and brackish water throughout the 

 year. There appears, however, to be excellent evidence that some of the Lampreys move from, 

 brackish water into fresh for purposes of spawning. 



Benecke, speaking of the habits of the river Lamprey of the Baltic, remarks: "Concerning the 

 habits of 'Nine-eyes' in the sea nothing is known. In summer they make their way from the 

 Baltic into the Kurisches Haff and the Frisches Haff, and toward the end of September begin to 

 ascend the rivers, and are caught in great numbers in baskets and. pots. The ascent continues 

 until January. In the upper reaches of the rivers they make their appearance in the early spring, 

 and spawn in April and May in small schools in shallow places, where the water flows rapidly 

 over shingly bottom. The act of spawning has been observed by us from year to year in the 

 passage between the bridges at' Brauusberg. After the eggs, which are one millimeter in 

 diameter, grayish-yellow in color, and entirely opaque, have been deposited in little masses, the 

 Lampreys die. 



" The development of the spawn is extremely dependent upon the weather, so that dining 

 many years only a very small brood of young fishes makes its appearance. The young of this 

 species have been found by August Miiller in the Oder and the Alle, and in the latter (?) the 

 drying up of one of its tributaries near the mill at Pinne gives an opportunity every year to collect 

 hundreds of them in the bottom mud. They are never found partially grown, and we must believe 

 that they go back to the sea, there to attain their full size." 



REPRODUCTION. Concerning the breeding habits of the brook Lamprey, P. planeri, Beuecke 

 writes : " The brook Lampreys, like the allied species, feed upon little animals, and are found in almost 

 all the dear brooks in Prussia, seeming never to migrate to the sea, although Yarrell claims that he 

 has found them there. The clear gray or grayish-yellow eggs, which are one millimeter in thick- 



