158 VERTEBRATE ZOOLOGY 



tion of its gills suggest that these organs play a more important 

 r61e in breathing than in either Protopterus or Lepidosiren." 



The genus Protopterus (Fig. 95, B) has a wide range over the con- 

 tinent of Africa and consists of three species, P- annedans, P. 

 mthiopicus, and P. dolloi. These fishes inhabit the marshes near 

 rivers, living upon frogs, worms, insects, etc., that abound in 

 marshy places. The long slender fins are used probably as tactile 

 organs though they may help in locomotion along the bottom. 

 During the wet season they live and breathe much as does Neoceratoi 

 dt<5. 



"In the dry seasons," says Bridge, "the marshes in which 

 Protopterus lives become dried up, and to meet this adverse 

 change in its surroundings, the Fish hibernates, or passes into a 

 summer sleep, until the next rainy season brings about conditions 

 more favorable to active life. Preparatory to this summer sleep, 

 and before the ground becomes too hard, the Fish makes its way 

 into the mud to a depth of about eighteen inches, and there 

 coils itself up into a flask-like enlargement (Fig. 95, D) at the 

 bottom of the burrow, which is lined by a capsule of hardened 

 mucus secreted by the glands of the skin. The mouth of the 

 flask is closed by a capsular wall or lid, which is perforated by a 

 small aperture. The margins of this aperture are pushed inwards, 

 so as to form a tubular funnel for insertion between the lips of 

 the Fish. While encapsuled in its cocoon the Fish is surrounded 

 by a soft slimy mucus, no doubt for the purpose of keeping the 

 skin moist, and its lungs are the sole breathing organs, the air 

 pouring from the open mouth of the burrow through the hole 

 in the lid directly to the mouth of the animal. The nutrition 

 of the dormant Fish is effected by the absorption of the fat 

 stored about the kidneys and gonads, somewhat after the fashion 

 not unknown in the fat-bodies of Insects and the hibernating 

 glands of Rodents." 



Lepidosiren (Fig. 95, C) is just a step more terrestrial in its habits 

 than Protopterus and several degrees more degenerate than the latter. 

 It lives in swamps, breathes air more largely, taking several breaths 

 at a time when it comes to the surface. In the dry season it digs a 

 burrow deeper than that of Protopterus. It even lays its eggs in deep 

 burrows in the black, peaty soil of the swamps in which it lives, 



