730 PBOCEEDINGS OF THE NATIONAL MUSEUM. 



that the specimen from AVukunom-u. with the short snout, may belong 

 to :i distinct species. In ueneral, the example tioinvd ])v us (from off 

 Enoshima: Collection of U. S. Fish Connnission steanier A//n/fro.s.s) 

 aorees with Schleg-eFs plate. 



With the species of Myxhu, this species is known to the Japanese 

 fisherman as jShdaunagi or slime-eel. The two species are alike in 

 size, color, and hal)it. Eptatretus hurgeri may he known hy the pres- 

 ence of six gill openings on each side, instead of one. l)v tluMery blunt 

 upper lip or tip of snout, and by the paler edges to the tins. The eye 

 is much more distinct than in Jfyxine. 



^ Named for its discoverer. Burger, who collected for Siebold and 

 Schlegel. 



Family III. MYXINID^F]. 



Body eel-shaped, covered hy a thin skin, which is easily detached. 

 Along the lower side, for nearly the. whole length of the animal, arc 

 two rows of mucous glands, each with an external opening, yielding 

 an al)undance of nuicus, which renders these animals excessively slimy! 

 No eyes. Brain small, of the normal tish type. Skull little devel- 

 oped, cartilaginous: the flexible notochord inclosed in its sheath and 

 extending from the base of the skull to the end of the tail, represent- 

 ing the spinal cohunn. ^k)uth round, suctorial, without lips, with a 

 few barbels on each side. Nostril single, large, on the median line 

 above, and at the very front of the head, provided with two pairs of 

 barbels. Teeth strong, a single median one on the roof of the mouth, 

 and two rows on each side of the tongue, which is a powerful organ,' 

 with a strong, tiln-ous tendon moving in a muscular sheath. Alimen- 

 tary canal a simple, nearly straight tube, without spiral valve; gill 

 sacs placed on each side of the (esophagus, lying directly against ^'its 

 outer walls. The water passes into them hy a small pore opening 

 directly from the (esophagus into each sac. It is then passed out ])y a 

 duct, which continues backward along the outer walls of the sacs to 

 the abdominal wall at the end of the last sac, where all the ducts from 

 one side unite into one. and the water is emptied at the branchial open- 

 mg on each side of the median line. In close comiection with the 

 branchial opening on the left side there is a third opening that leads 

 by a very short duct to the (esophagus, and hence into the branchial 

 sacs, at the times when the supply of watei- is cut off by the head ])eing 

 buried in the flesh of the animal on which it feeds. Vent close to tip 

 of tail. Ovary single, on the right side. No oviducts; the mature 

 eggs falling into the abdominal cavity and excluded through the peri- 

 toneal opening at the side of the vent. Eggs with a horny case, and 

 threads for adhesion. Parasitic anhnals, burrowing into the })odies of 

 fishes, and found in the cold seas. One genus, with several species, 

 found in most cold seas. 



