612 ON THE FAT-BODIES OF THE SAUROPSIDA. [DeC. 3, 



Monitors do not seem to show any special approximation to the 

 Crocodiles ; and in this respect the only important difference between 

 the former and other lizards appears to be that the lungs do not lie 

 in the same cavity with the liver. It is doubtful if this difference 

 is of any importance to the systematist. 



VIII. EXPLAJSTATION OF PLATES LIX. & LX. 



al. alimentaiy canal. 

 ao. dorsal aorta. 

 a.v. vitelline artery. 

 bl. urinary bladder. 

 CM. corpus adiposum (fat -body). 

 ca.c. circumadiposal cavity. 

 cr.c. circumrcnal cavity. 

 CIV. Wolflan body. 

 ff. genital gland. 

 h. liver. 



m. median septum (mesentery or ligaments supporting alimen- 

 tary canal). 

 n. central nervous system. 

 0. ovum. 

 od. oviduct. 

 pp.c. pleuroperitoneal cavity (main body-cavity). 

 2nd. lung. 

 pv. pelvic girdle. 

 re. kidney. 



v.a. anterior abdominal or allautoie vein. 

 v.c.i. vena cava inferior. 

 v.d. vas deferens. 

 v.v. vitelline vein. 

 a. puhnohepatic ligament. 

 2'. fuhnohepatic recess of left side. 



Figs. 1-17. Transverse sections of Lizards and Snakes (chiefly the former), to 

 show the relations of the fat-bodies and circumadiposal sj^aces to the 

 pleuroperitoneal cavity and the general relations of the abdominal 

 vieera. 



Figs. 1-7. Transverse sections of advanced embryo of Amphisbcena darwinii, 

 dravrn from behind. The sections are in order from before back- 

 wards. 



Fig. 8. Transverse section of common Adder, taken at such a place that it 

 passes through both kidneys. 



Fig. 9. Transverse section of advanced embyro of the common Grass-Snake, 

 through one kidney and the embryonic genital gland. 



Fig. 10. Transverse section of adult § of common Grass-Snake, through one 

 kidney ; a large egg in the duct (distorted) fills most of the body- 

 cavity. 



Fig. 11. Transverse section of a specimen of Lacerta, in which the fat-bodies 

 wei-e specially well developed and extended forward further than 

 usual. 



Fig. 12. A more posterior section of the same animal, through the region of the 

 kidneys, showing that in some regions the peritoneum hardly wraps 

 round the kidneys or fat-bodies at all. 



Fig. 13. A transverse section of another specimen of Lacerta wW&'s, showing 

 a similar relation of the kidneys to the peritoneum in the region 

 chosen. 



Figs. 14-17. Transverse sections of a young Monitor niloticus. The sections in 

 order from behind forwards. 



We note here that the circumadiposal cavity extends forwards ventral to. the 



