PISCES 



155 



thing like an Amphibian limb impossible. Certain specializations 

 are also present, such as the fusion of teeth into massive grinding or 

 tritoral plates, the development of respiratory filaments on the pelvic 



Fia. 95. — Group of Lung-Fishes (Dipneusti). A, N eoceratodus Jorsleri, Queens- 

 land. B, Protopterus anvectmis, Gambia. C, Lepidosiren piaradoxa, Paraguay. 

 (The lozenge-shaped markings in B do not represent scales, but areas of skin 

 outlined by pigment cells. In a fresh specimen the scales are completely invis- 

 ible, as in C.) D, Diagram of Piotopleius aestivating in the mud, showing the 

 body coiled up and the mucous sac with tube leading to mouth. E, Larva of 

 Protopterus on the seventh day, showing cutaneous gills, cement organ under 

 head, and narrow paired fins. F, Larva of Lepidosiren- thirty days after hatching, 

 showing some characters as E. (Redrawn from Bridge, A, after Giinther; B, and 

 C, after Lankester; D, after Parker; E, after Budgett, and F, after Kerr.) 



