bo 
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Cc. M. JACKSON 
MATERIAL AND METHODS 
The material used included the suprarenals from 108 albino 
rats (Mus norvegicus albinus), obtained partly in connection 
with my previous studies (15 a and 715 b), partly, from material 
collected by Hoskins (’16) and Stewart (’16), and partly from new 
material. The 108 rats include 52 normal (control) rats of both » 
sexes, varying from new-born to about one year of age; 16 young 
rats held nearly at maintenance (constant body weight) or se- 
verely stunted by underfeeding for various periods; 10 rats refed 
after such underfeeding and 1 refed after acute ananition (adult) ; 
13 adult rats subjected to acute inanition; and 6 subjected to 
chronic inanition (table 1). 
The diet in all cases was whole-wheat (graham) bread soaked 
in whole milk, the amount being reduced during the maintenance 
and chronic inanition experiments and cut off entirely in acute 
inanition. Water ad libitum was supplied in all cases. In the 
chronic-inanition experiments the amount of food was gradually 
reduced through a period of about five weeks. The percentage 
losses and final body weights are given in tables 1 D and 1 E. 
In order to keep the animals alive during the longer experi- 
mental periods, especially in the case of the young rats underfed 
for long periods, it was found necessary to keep them in a warm 
room. ‘The cages were provided with wire-net bottoms to pre- 
vent the rats from eating their feces. 
The general data for the individual rats used are Sica in 
table 1. In the first column the letters indicate the series to 
which the rats belong. ‘The number preceding the decimal point 
is the litter number and the number following designates the indi- 
vidual rat. In several of the rats used for adult acute- and 
chronic-inanition tests, however, the litter records were not avail- 
able. The sex, age (where known), nose-anus length, gross body 
weight (in some cases also net, without intestinal contents), and 
the fresh weight of both suprarenals are recorded in the table. 
In the subsequent tables 2, 3, and 5, the data are usually 
grouped for economy of space. The individual data will be filed 
in The Wistar Institute of Anatomy, Philadelphia, where they 
may be consulted by those interested. 
