DISCUSSION OF SPECIES AND THEIR DISTRIBUTION. 3 



tities and with wonderful rapidity. A single hag will till a two-gallon bucket with slime 

 mingled with water in a few .seconds, and after a slight interval can repeat the operation 

 with ease. The ei:u's are elliptical in shape, and are supplied at each end with numerous 

 short threads for adhesion. Nansen has made an exceedingly interesting investigation into 

 the hermaphroditism of this form. 



Myxine occurs only in the North Atlantic. On the coasts of Europe it is found in the Nor- 

 wegian Fiords as deep as 70 fathoms, and it ranges as far south as Newcastle and the Firth 

 of Forth. In the western Atlantic it is known to occur on the offshore banks as far north 

 as the Grand Bank of Newfoundland, and probably still farther north through the Arctic 

 Sea; and it also occurs on the shoals in the Hay of Fundy, one of the best known colonies 

 being on the cod bank to the eastward of the north end of the island of Grand Man an. 

 The fishermen of the offshore banks frequently pull them to the surface clinging to the fish 

 taken on their hooks. In the deeper waters of the western Atlantic they have been found 

 as far south as lat. 38° 31', Ion. 73° 25', off the capes of Delaware by the Fish Commis- 

 sion at a depth of 126 fathoms, and off Cape Fear, North Carolina, lat. 34°, Ion. 76° 10', 

 at a depth of 178 fathoms. Off Marthas Vineyard they have been found by the Fish Com- 

 mission at a depth of 264 fathoms, with a temperature of 47°, and farther out at sea in the 

 same region by the Blake at 304 fathoms (lat. 40° 11' 40", Ion. 68° 22'), and 524 fathoms 

 (lat. 41° 32', Ion. 65° 55'). 



The form is so abundant off the New England coast in depths of 100 to 250 fathoms that a 

 record of all the localities of its occurrence has not been kept. It is known, however, that 

 specimens were obtained from the following stations of the Blake: 309, 306, and 327; and 

 also from the following stations of the Fish Commission steamers: 8G9, 870, 871, 878, 939, 

 951, 1038, 1047, 1154, 2080, 20SX, 2089, 2092. 



MYXINE AUSTRALIS, Jenyns. (Figure 2.) 



Myxine australis, Jenyns, Voyage of H. M. S. Beagle, Zoology (edited by Charles Darwin), 1839-'43; Fishes; 

 • 159; Gcnther, Cat. Fish. Brit. Mas., vm, 1870, 511; Challenger Report, xxn, 1887, 2157. 

 ffeptatrema oirrhatum, Schlegel, Fauna Japonlca, Poissons, 310, pi. 143 (fide Giinther). 



A Myxine with ten or eleven slender teeth in each of the two series; the three foremost 

 strongest and confluent at the base, the other teeth remaining separate; in the second 

 series the two innermost teeth are confluent at the base. 



,1/. australis was first described from Sandy Point and the Tyssen Island, at the south- 

 ern extremity of .South America. It. was found by the Challenger in the Japanese Sea, 

 where six specimens from 9 to 20 inches in length were taken on the Hyalonema ground at 

 a depth of 345 fathoms (Station 232). Dr. Giinther isof the opinion that Heptatrema oirrha- 

 tum Schlegel, from Japan, should be referred to the same species. The Challenger obtained 

 specimens of M. australis from the Straits of Magellan, and the species is most probably an 

 inhabitant of the deeper waters to the east of Patagonia, and entitled to a place in the 

 fauna of the Atlantic basin. 



Order HYPEROARTIA. 



Cyclostomata hyperoartia, Miller, Abhandl. Akad. Wiss., Berlin, 1834, 77. 

 Ryperoartia, Gill, Johnson's Cyclopaedia, n, 1079. 



Au order of Marsipobranchiates distinguished by the development of the skull and the 

 eoecal nature of the median external nasal aperture; no duct perforating the palate, which 

 is, therefore, left entire (whence the name). The branchial apertures are on each side 

 behind the head, and seven in number; the inner branchial duets debouch into a separate 

 common tube. The ova are small and superficially like those of fishes. The young undergo 

 a complete metamorphosis after leaving the egg. The larva' have an elongated slit-like 

 mouth, and are without teeth or eyes. In this condition they were formerly considered to 

 be members of a peculiar group (Ammocoetes). At maturity the mouth is circular, surrounded 



