484 



PARENTAL CARE AMONG FRESH-WATER FISHES. 



fourth side was several inches lower, being about two inches below the 

 surface. The deepest part of the nest was opposite to that side where 

 the wall was low, the bottom being about six inches below^ the surface 

 of the water.'' Such were the typical nests observed by Budgett. 



In one nest " were deposited about a thousand spherical amber-like 

 eggs 10 millimeters in diameter. The eggs hatched five days after 

 being laid, and in eighteen days a thousand young fry," about three 

 inches long, left the nest. They were then essentially like the 



adults. Many of the 

 young were secured by 

 Budgett immediately af- 

 ter they had left their 

 nest, and " lived well on 

 chopped-up worms.'' He 

 tried to take some to 

 England, but every one 

 died as soon as they 

 " got into colder climes." 

 The native Africans 

 " approach these nests 

 with great caution, stat- 

 ing that the jiarent is at 

 this time extremely fierce and has a very formidable bite." 



Fig. G8. — Gymiuirchvs niloticus, larva, 6 days alter 

 hatchini;, showing long drawn out yolk-sac and 

 abundant external gill-fllaments. After Budgett. 



THE OSTEOGLOSSOIDEANS. 



In the fresh waters of various tropical countries are found certain 

 fishes which have a general resemblance to some of the ganoids of 

 old times, and one of them, at least, has a complexity of the lower 

 jaw which is only i:>aralleled by such ganoids as the Amiids and 

 Lepidosteids. The group containing such forms has been designated 

 as a peculiar superfamily — Osteoglossoideans. 



The body is elongated and covered with a system of hard scales 

 having a peculiar sculpture, the field being divided into many areas, 

 resembling mosaic work; the head is externally bony and sculptured, 

 and the parietals intervene between the frontals and supraoccij^ital. 

 By some naturalists three families have been recognized for such 

 fishes, but they are generally united under one — Osteoglossida\ All 

 agree in having the intermaxillaries paired and in the possession of 

 well-developed interopercles and subopercles, and thus differ from 

 their nearest relatives, the dwarfed Pantodontids of Africa. The 

 life histories of these forms are little known, but two of the represent- 

 atives of the group have been ascertained to be care takers of eggs 

 and young, and verj^ interesting details have been made known of 

 one of them. 



