THE FAT-BODIES. 



349 



borders are g-iven off fing-er-like processes ; these may divide dicho- 

 tomoiisly either near the base or more peripherally. The external 

 processes are much the longest^ and in the male often conceal the 

 greater part of the testis (Fig". 236 FK). The organs vary greatly 

 in size with the season of the year. 



Fig. 227. 



Two prepiiiations from the fat-body of Rana esculenta 1. — G. H. 



I. Section of fat-body, stained with borax-carmine (Hartnack, Oc. I, Syst. 7). 

 6 Fat-cells, 

 c Adenoid tissue. 

 II. Tliree lobes of fat-body of Rana esculenta ; coai'sely injected (Hartnack, Oc. I, Syst. 3). 

 Arteries striped. Veins shaded. 



b. [Minute structure. Each organ is completely surrounded by 

 peritoneum, under which is a very fine layer of connective-tissue. 

 The interior of the organ (Fig. 227 I) consists of large fat-cells 

 with small patches of adenoid tissu.e interspersed. The organs are 

 extremely vascular; each lobe has a main artery which gives off 

 lateral branches : each of these immediately divides to form two 

 vessels, which run in opposite directions and almost parallel with 

 the main stem ; the vessels then break up into a fine network of 

 capillaries.] 



' From specimens collected in November. 



