THE FISHES OF ,\LASKA. 271 



50. Diaphus theta Eigenmann & Eigt'nmann. 



One specimen 2.5 inches lung dredged at station 42G7, off Mount Edgecumbe in 922 fathoms. 

 Head 3; depth 4.5; eye 3; snout about 3 in eye; dor.sal 12; anal 9; pectorals 12; lateral line 35. 



Family i8. CHAULIODONTID^. 



51. Cyclothone microdon (Giinther). 



Recorded by Gilbert (1895) from Albatross stations 3307 and 3308 in Bering Sea. Not taken liy us. 



52. Chauliodus macouni Bean. 



One specimen 4.25 inches long from station 4231, Behm Canal near I^oring. and another 3.5 inches 

 long from station4 257, in Lynn Canal. Also recorded from .station 3340, south of Alaska peninsula 

 (Gilliert 1895;. 



Family it). PLAGYODONTlDiE. 



53. Plagyodus sesculapius Bean. 



Originally described by Bean (1884) from Iliuliuk, Unalaska. Recorded also from Simimer 

 Harbor, Unalaska (.Jordan & Gilbert 1899). 



Fig. 20.— Plagyodus a'sculapius Bean. 

 54. Plagyodus boreaUs (Gill). 

 Recorded from Captains Harbor. Unalaska (Bean 1882). 



Family 20. NOTACANTHID^. 

 55. Macdonaldia challeugeri (Vaillant). 

 Recorded by Gilbert (1895) from Albatross station 3308 in Bering Sea. 



Family 21. DALLIID^. 

 56. DaUia pectoralis Bean. 



This interesting fish, which is the sole representative of a family and order of fishes, was first 

 described by Bean (1880), from specimens collected by its discoverer. Dr. Dall, at St. Micliael. 

 Specimens were also reported by Nelson (1887) from Andreafski, Yukon River, and mouth of Tanana 

 River, and by Gilbert (1895) from Nushagak River. It occurs in great numliers on St. Lawrence 

 Island. We have Ijut a single specimen, one secitred Ijy Gilbert. Although so abundant in Alaska, 

 this species is rare in museums and collections in general, illustrating the well-known fact that the 

 commonest forms in nature are often the rarest as preserved specimens Turner (1886) says: 



This species is probably the most abtmdant of all the fishes which occur in the fresh and brackish 

 waters of the northern part of Alaska. It is found in all the small streams of the low grounds, in the 



