74 BULLETIN 208, UNITED STATES NATIONAL IMUSEUM 



unchanged. A very abrupt change is to be noted, however, between 

 it and wax from the intestines, which requires more than twice the 

 temperatiu-e to begin to soften or to run or to be fully melted. The 

 wax from the upper part of the small intestine has some foreign matter 

 with it, not identifiable with anything from a waxcomb but probably 

 from some of the other food items eaten by the bird. The wax from 

 the lower part of the large intestine is interpretable as consisting of 

 the components of the original wax ingested that were not digested 

 and assimilated. As far as may be judged by tests from the alimentary 

 tract of a single bird it appears that those elements in the wax that 

 have relatively low softening and melting points are assimilated as 

 the material passes into the small intestine. 



A word of explanation msij be pertinent regarding the fact that the 

 unassimilated components of the wax have softening and melting 

 points so very much higher than the original wax as ingested. Dr. 

 Warth informs me that in beeswax there are some very high melting 

 point components which, when combined with calcium or other 

 inorganic matter, will give extremely high melting point substances. 

 It seems that something of that sort may have transpired in the 

 intestinal tract of the honey-guide. 



Further analyses made for me by Dr. F. P. Veitch, Professor of 

 Physiological Chemistry, University of Maryland, yielded the follow- 

 ing pertinent information: Two specimens of washed, dried, wild 

 bee comb from South Africa, such as the birds feed on normally, 

 contained silicon, phosphorus, magnesium, aluminium, calcium, 

 copper, iron, sodium, nickel, and zinc; one of them also contained a 

 trace of boron. Other elements not detected by an arc but which 

 may have been present in addition to oxygen were chlorine, sulphur, 

 nitrogen, fluorine, and iodine. Of the elements present, magnesium, 

 phosphorus, silicon, and calcium were found in the greatest quantity; 

 iron, zinc, sodium, and nickel in lesser amounts. 



These two samples of bee comb had low saponification numbers, 

 49 and 45 mg. KOH/gm., the saponification value given for ordinary 

 commercial beeswax being 80. It ma}^ be explained that the saponifica- 

 tion value or number is the number of milligrams of potassium hydrox- 

 ide required for the complete hydrolysis of one gram of the wax or 

 other substance being examined. The saponification value varies 

 inversely with the molecular weight of the fatty acids included in the 

 wax. The lower the molecular weights of these constituents the more 

 readily available they are for assimilation as food by the bird eating 

 the substance, so it follows that if any of the wax components were 

 rendered available to the bird, and were assimilated by it during the 

 digestive process, this should be reflected in increasing saponification 

 values of the wax samples from successively posterior portions of the 



