The microvasculatures of the lungs of the Rhabdophis tigrina lateralis and the Phrynocephalus frontalis Strauch are studied by scanning electron microscopy using corrosion casts.The pulmonary microvascular anatomy is distinctly different in these two species.There were many reticular,secondary and third septa and alveolar septa on the inner surface of the lung wall of the Rhabdophis tigrina lateralis,which separated the inner surface of the lung wall into a lot of sac room,small room,subordinate small rooms and pulmonary alveoli.There were only reticular and secondary septa and alveolar septa on the inner surfaces of the lung walls of the Phrynocephalus frontalis Strauch,so that the inner surface of the lung wall were separated into many small rooms,subordinate small rooms and pulmonary alveoli.The reticular septa on the inner surface of the lung wall were obviously sparse in the Phrynocephalus frontalis Strauch than in the Rhabdophis tigrina lateralis.There were plenty of capillaries in every kind of septa and walls of the pulmonary alveoli of the animals,which anastomosed with each other to form a single layer of dense network.The diameters of the alveolar capillaries in the Rhabdophis tigrina lateralis, Phrynocephalus frontalis Strauch were 7.5～13μm,6.5～(12.5μm)and the diameters of their mesh were 5～42μm,6～25μm respectively.In addition,the relationship among the microvasculature of the animals’ lung and respiratory efficiency were also discussed.
