OCEANIC ICHTHYOLOGY 



BASED UPON A STUDY OP 



THE DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



By Georue Brown Goode and Tarleton H. Bean. 



A DISCUSSION OF THE SPECIES AND THEIR DISTRIBUTION. 



Class MARSIPOBRANCHIl. 



Marsipohranchii, Bonaparte, Trans. Liun. Soc. Loudon, v. 18, \t\t. :iS9, 304, 1<S41. 

 ilarsij)i>hra>ichia, GlLi., .Johnson's Cyclopa'dia, III, 31fi. 

 Vermupteri (part), Owen, Auatumy of Vertebrates, i, 7. 



Skeleton of ;i very inferior type, tlie uotocliord or embryoual vertebral coluinn being 

 persistent. Skull rudimentary and represented by a small brain ease and capsules for 

 the organs of sense (auditory and olfactory), as well as by an ethmovomerine i)late; tlie 

 inferior appendages developed as elements designated as the "subocnlar areli," with a 

 metapterygoid or "superior quadrate" and an "inferior (luadrate" portion, the "palato- 

 pterygoid" element, and the "stylohyal process;" labial cartilages form also a prominent 

 feature of the skull; bones or cartilages, representing the upper as well as the lower Jaws, 

 entirely wanting; the branchial apparatus sustained by a basket like skeleton; no limbs 

 developed, and no scapular arch or pelvic girdle. Brain small but distinctly developed, 

 differentiated into the brain i)roper and medulla oblongata; the former composed, as in the 

 higher forms, of the " mesencephalon," " thalamencephalon," " prosencephalon," and " rhinen- 

 cephalou;" the latter small, with a fourth ventricle conspicuous from above, and the "cere- 

 bellum" very rudimentary. Auditory apparatus quite simple, represented by a single mem- 

 branous tube without any dittereutiatiou into canals and vestibules, as in the Hyperotreta, 

 or, at most, as in the Hyperoartia, with two semicular canals and a sacculated vestibule. 

 Olfactory apparatus consists of a median sac; is provided with but a single external aper- 

 ture. Heart distinctly developed and divided into an auricle and ventricle, the former hav- 

 ing in front a venous sinus, and the whole inclosed in a "pericardium," which connects with 

 the peritoneal cavity. Intestinal canal simjile; liver specialized as such, and kidneys well 

 developed, with ureters opening behind into the rectum. Organs of g(;neratioii without 

 ducts, discharging into the abdomen, from which the products depart by an abdominal pore. 



The species of the class are found in both fresh and salt waters, the retroniyzontids 

 having members in the fresh and salt waters of all temperate and subtemperate countries; 

 while the Myxinoids are represented in the cold waters of the northern hemisphere by 

 Myxine, as well as along the shores of a considerable i)ortion of the Pacific — in the 

 Japanese and Chinese seas, California, Chile, and Australia. 



19868— No. 2 1 1 



