ZOOLOGICAL SOCIETY BULLETIN 



1335 



THE MUD PUPPY OR WATER DOG. 



THIS large American salamander {Nectur- 

 iis maculosus) is nearly always to be 

 found on exhibition at the Aquarium, and 

 an excellent j^hotograph of it is presented in this 

 Bulletin. 



It is an inhabitant of the Great Lakes re- 

 gion and the Mississippi Valley. An allied spe- 

 cies is found in North and South Carolina. Its 

 conspicuous external gills enable anyone to dis- 

 tinguish it from another large salamander of 

 the upper Mississippi region, the hellbender 

 (^Crypiohranchus allegheniensis) which it re- 

 sembles in size and general appearance. 



The food of the mud pupp}^, which is entire- 

 ly aquatic in its habits, consists, of the smaller 

 water animals, crayfishes, small fishes, mollusks 

 and insects. 



In some parts of its habitat it is very abun- 

 dant, as in Michigan and Illinois, where hun- 

 dreds have been hooked or seined in a single 

 day. It is an abomination to anglers, who sac- 

 rifice their hooks rather than handle the slimy 

 creature in detaching them. The mud puppy 

 lays its eggs in May and June under the shelter 

 of a stone to which each egg is attached by a 

 gelatinous stalk. 



It reaches a length of eighteen inches or 

 more. The largest specimen in the Aquarium 

 is about twelve inches long. — C. H. T. 



THE DrXN DIVING-HOOD IX USE 

 Photographed by Submarine Photo Co.. Miami, Fla. 



LONGLEY'S AND REIGHARD'S STUDIES 



OF THE REEF FISHES OF THE 



TORTUGAS, FLORIDA. 



By Alfred G. Mayer. 



THE colors of tropical fishes inhabiting 

 coral reefs are brilliant and varied. 



It has remained for Professor Longle}^ 

 to show that protective and not warning color is 

 dominant among such fishes. 



The fishes of the mackerel tribe, blue above 

 with silvery yellow-spangled sides and glisten- 

 ing white belly fade into the background of the 

 universal blue if one sees them as other fishes 

 see by going down equipped with a diving 

 helmet. 



Such a helmet has been invented by Mr. 

 Dunn of Miami, Florida, and it literally en- 

 ables one in a moment to become for all intents 

 and purposes a fish among the fishes of the 

 reefs. 



It was onlj^ after years of patient study that 



Professor Longley discovered the clue to this 



paradox of the brilliant color of these tropical 



I fishes, yet if one considers their habits and 



takes them in their normal surroundings they 

 are found to be protectively colored, and hid- 

 den by many interesting devices fromi the eyes 

 of their enemies. Often the fishes are observed 

 to change from green to gray as they glide from 

 the grassy bottom on to the sandy floor, and 

 curiously at sunset many of the blue, yellow 

 and green fishes bury themselves under the 

 sand, so that the commonest daj'-time reef 

 fishes are not to be seen at night. 



At Tortugas one of our rarest fishes was the 

 Apogon — "the marine goldfish," bright red with 

 a black spot upon his side, and a huge eye, and 

 only once or twice in a whole season did we 

 find one. Now, however, due to Professor 

 Long-ley's discovery, we know that they are the 

 commonest fishes of the reefs after sunset, for 

 when the blues, yellows and greens have gone to 

 bed beneath the sand the marine goldfishes 

 come out from many a hiding ]ilace. In fact 

 Longley finds that red fislies witli large eyes 

 are nocturnal, and this is interesting for the 

 "Michel Sars" deep-sea expedition proved that 

 red rays were the soonest to be absorbed as 

 light passed through the water. TIius in the 



