1889.] FAT-BODIES OF THE SAXJROPSIDA. 605 



pointing backwards, which in the hinder region extends up the sides 

 as far as the kidneys. 



I believe that the views to which I have been led largely agree 

 with those of Mr. Beddard\ We agree that the condition in Monitors 

 to which he has drawn attention is unlike that in other Lizards and 

 well worthy of study. There are, however, certain of his conclusions 

 and suggestions which, after a careful examination of Monitors - and 

 other reptiles, I am unable to accept. 



Beddard says (1, p. 100) : " In Monitors when the body- 

 walls are cut open and reflected, the alimentary viscera are not 

 exposed as they are in Iguana. A loose membrane covers the 

 viscera ; the membrane looks as if it were simply the lining 

 peritoneum of the abdominal cavity which had got separated and 

 detached from the abdominal parietes ; this is, however, not the 

 case ; an examination hy the aid of the microscope shoiued clearly that 

 a layer of peritonetim covers the abdominal musculature, and is quite 

 distinct from the horizontal membrane ; in Varanus griseus the 

 'peritoneal layer was particularly distinct, for the reason that it 

 contained numerous pigmented corpuscles. . . .This horizontal mem- 

 lra7ie also separates the kidneys from the reproductive glands ; the 

 latter lie internally to it ; the kidneys are placed outside it." 



The italics in the above quotation are mine, and serve to indicate 

 the passages to which I would cell attention. 



It is certain that the space surrounding the fat-bodies and 

 separated from the peritoneal cavity containing the intestines, by 

 the "horizontal" membrane that wraps round these, is not due 

 merely to some accidental or post-mortem separation of this mem- 

 brane from the body-wall ; and that the space in question, which I 

 will term the circumadiposal cavity {ca.c, in figs. 14-17), is lined by 

 a smooth membrane which covers the body-wall, and is reflected to 

 form the exterior layer of the so-called " horizontal membrane." 



I presume that, in saying that the microscope shows this lining 

 membrane to be peritoneum, Beddard merely means that it forms a 

 natural free surface, and is not a rough line of parting produced by 

 a tear. More than this the microscope could not well prove ; nor 

 does the presence of pigment do so, since pigment, though common 

 in the peritoneal lining of the body-cavity,is not confined to this layer. 

 It may occur in the more external and muscular layers of the body- 

 wall, as can be seen in transverse sections of Snakes. 



Now, in no reptile examined have I observed any connection 

 between the peritoneal cavity proper and the circumadiposal 

 cavities; and since (as Beddard, judging by his paper (1, p. 100), 

 would admit) the circumadiposal cavities of the Monitors are 

 homologous with the inconspicuous spaces round the fat-bodies in 

 other Lizards, which there is no good reason to regard as parts of 

 the peritoneal cavity, I hold that until such a connection shall 



^ I would acknowledge the kind and practical interest that Mr. Beddard has 

 taken in my work. 



^ I have examined two specimens of Varanus indicus, two of V. niyro- 

 punctatus, and some ten small specimens of V. niloiiciis. 



