November-December, 19 US 



CHICAGO NATURAL HISTORY MUSEUM BULLETIN 



Page 5 



REGALECUS, LAMPRIS, MOLA AND RANZANIA— FOUR 



OF THE STRANGEST FISHES TO BE FOUND IN THE SEA 



different in appearance, is systematically 

 close to Regalecus, the evidence of relation- 

 ship resting upon the peculiar structure of 

 the jaws. It, too, is an oceanic fish, and 

 though it probably lives somewhat below 

 the surface, down to around 100 fathoms, 

 the body structure is not typically deepsea. 

 It is an excellent food fish, but is only rarely 

 caught on hook and line. 



Although the moonfish may be six feet 

 long, its toothless mouth is adapted for 

 capturing only the smaller fry of the sea 

 and practically nothing is known about its 

 manner of living. Almost circular in shape, 

 it weighs up to about 600 pounds. The 

 chief haunts of the fish are the warm waters 

 of the oceans; but it ranges as far north as 

 Newfoundland and Finland in the summer. 



By MARION GREY 



ASSOCIATE, DIVISION OF PISHBS 



Models of four of the strangest fishes to 

 be found in the sea have recently been 

 installed in the systematic cases along the 

 north wall of the Hall of Fishes (Hall O). 

 Only one of them, indeed, is familiar even 

 to the professional fishermen of the seacoast. 

 It is the ocean sunfish (no relative of the 

 fresh-water sunfishes). So remarkable are 

 these creatures, however, that the names: — 



Regalecus, the oar fish ; 



Lampris, the moonfish; 



Mola, the sunfish; 



Ramania, the truncated sunfish — 

 are familar to all zoologists who study 

 salt-water fishes. 



One of the newly installed forms, the oar 

 fish {Regalecus glesne), has sometimes been 

 mistaken for a "sea serpent." It nicely fits 

 the description, albeit imaginative, of a 

 monster with a horse's head and flaming 

 mane. The thin silvery ribbon-like body, 

 almost as flat as a pancake, has been known 

 to reach a length of 50 feet, ample size for a 

 monster, while the illusion is completed by a 

 crest consisting of the first rays of the long 

 crimson dorsal fin. It may weigh as much 

 as 600 pounds. 



OAR FISH RARELY SEEN 



The oar fish, also called ribbonfish, is 

 probably an inhabitant of the upper parts 

 of the dark waters of the oceans. Its depth 

 range is entirely unknown since the fish has 

 never been caught on lines, or in dredges or 

 deep-sea nets. Besides the one or two 

 instances of observation of the living animal, 

 our "sea serpent" is known only from dead 

 specimens found washed ashore, usually 

 following a storm. 



However, a certain amount of surmise is 

 possible. The middle depths of the sea, 

 between 500 and 1,000 fathoms, seem to be 

 inhabited characteristically by silvery and 

 sometimes reddish animals. That Regalecus 

 normally dwells in deep water is evident 

 from its thin bones and fragile watery flesh, a 

 condition not found in surface fishes. It is 

 useless for food purposes. 



THE MOONFISH 



The moonfish (Lampris luna), wholly 



OCEAN SUNFISH 



The giant ocean sunfish (Mola mola), 

 which grows to a length of ten feet, a height 

 of twelve feet, and a weight of more than a 

 ton, is a surface dweller, its name being 

 derived from a habit of lying on its side, 

 apparently basking in the sun. Like the 

 moonfish, it is confined to warm and tem- 

 perate seas, but there the resemblance ends, 

 for Lampris belongs to the more primitive 

 group of soft-rayed fishes, while Mola is a 

 highly specialized member of the Plecto- 

 gnathi, an assemblage of fishes that includes 

 puffers, trunkfishes, and trigger fishes. 



It is armored with a thick layer of hard 

 gristly material beneath the skin, almost 

 impervious to harpoons. It is harmless, and 

 sometimes allows a boat to come right 

 alongside with no attempt to escape. The 

 flesh, rarely eaten, is tough and tasteless. 



Unlike the oar fish and moonfish, very 

 young specimens of Mola are reasonably 

 common though not easily recognized. 

 They are tiny motes adorned with an array 

 of sharp little spines, which gradually dis- 

 appear as the larva grows into a sunfish. 



The related porcupine fishes possess a coat 

 of spines as adults, and many of the puffers 

 are covered, or partly so, with very small 

 prickles, a further indication that the devel- 

 opment of egg and larva tends to reveal the 

 evolutionary past of the individual. 



Our fourth model, of the truncated or 

 oblong sunfish (Ramania truncate), is no 



OCEAN SUNFISH OR MOLA 

 This odd creature grows to as much as 10 feet in length, 

 12 feet in height, and weighs in excess of 2,000 pounds. 



giant — its maximum length is about two 

 feet — but it provides an interesting contrast 

 to Mola. Both of these fishes belong to the 

 same family (Molidae), and although 

 Ranzania is a much smaller creature, its 

 relation to the giant sunfish is clear. The 

 most obvious differences are the smaller 

 size and the proportionately longer body of 

 Ranzania. Both species appear to have 

 had their tails chopped off, and their 

 mouths and heads are much alike. The dis- 

 tribution of the smaller species is similar to 

 that of Mola. 



The new models, as well as the sketches of 

 the larva, are the work of Staff Taxidermist 

 Leon L. Pray. 



Trustee Armour Returns 



Captain Lester Armour, U.S. Navy, a 

 Trustee of the Museum, has been released 

 from duty and returned to Chicago. Going 

 into war service with the rank of Lieutenant 

 Commander, he was successively promoted 

 to Commander and then Captain. He was 

 awarded the bronze star medal for his work 

 in organizing and directing special military 

 activities before and after D-day for the 

 invasion of the European continent. 



OAR FISH OR RIBBONFISH ^RKGALECUS) 

 Its dimensions, up to 50 feet in length although only about 10 inches high, together with the crest-like fin.rays on its head 

 and the flaming red ridge running the entire length of its back provide clues to the persistence of stories about sea serpents. 



Visiting Hours Change 



The Museum visiting hours, which have 

 been 9 a.m. to 5 p.m. daily during the autumn 

 months, will change to the winter schedule 

 — 9 A.M. to 4 P.M. — on November 1. These 

 hours will continue until February 28. 



