160 



Tests with Precipitins 



the precipitum-deficit. He represents this schematically by a figure 

 analogous to the well-known diagrams of Ehrlich, the lactoprecipitin 

 molecule being represented by a circle from which protrude an assumed 

 number (6) of receptors, the majority of which (4) represent specific 

 groups. Whereas the latter are alike, the individual groups (2) are 

 different, and the various combinations of the two lactosera (A and B) 

 and milks (a and b) are thus shown, the precipitable substance in milk 

 being fixed, or not, as the case may be, to receptors. See further under 

 " Individual Differences," p. 145. 



II. Haematosera. 



In the following pages the results of precipitin tests with haemato- 

 sera are given in the zoological order of the antisera, the tests made by 

 other observers being summarized in each case, the results of my tests 

 following. 



The number of tests, made by me with 30 antisera produced, is 

 given in the following table, the total number of tests being 16,000. 



Antisenim for 



Man 



Chimpanzee 



Ourang 



Cercopithecus 



Hedgehog 



Cat 



Hyaena 



Dog 



Seal 



Pig 



Llama 



Mexican Deer 



Reindeer 



Hog Deer 



Antelope 



No. of tests 

 therewith 



825 



47 



81 

 733 

 383 

 785 

 378 

 777 

 358 

 818 

 363 

 749 



69 

 699 

 686 



7751 



Antiserum for 

 Ox 



Sheep 

 Horse 

 Donkey 

 Zebra 

 Whale 

 Wallaby 

 Fowl 

 Ostrich 

 Fowl-egg 

 Emu-egg 

 Turtle 

 Alligator 

 Frog 

 Lobster 



7751 

 8249 



No. of tests 

 therewith 



790 

 701 

 790 



94 



94 



94 

 691 

 792 

 649 

 78'J 

 630 

 666 

 468 

 551 

 450 



8249 



Total number of tests 16,000 



In the short tables which follow, I have briefly summarized the general 

 results of the tests given in the experimental tables at the end, the object 

 of this being to render the conclusions clearer. The number of sera 



