Experimental Gigantism. 



ii 



used. In all instances, rabbits receiving subarachnoid injections 

 were paralleled by rabbits injected with identical amounts of the 

 same serum intravenously, and the bleedings and precipitin 

 tests of each were done at the same time. 



Summary: (i) Rabbits receiving a single dose (0.5 c.c.) of 

 normal horse serum into the subarachnoid space, produce pre- 

 cipitins in the blood in greater abundance, of higher titer, and 

 which persist longer than those in control rabbits receiving a 

 similar injection intravenously. 



(2) Repeated subarachnoid injections (0.5 c.c.) of normal horse 

 serum in rabbits, induce precipitins in the blood early. These 

 may appear in high titer as soon as one week after the initial 

 injection, whereas in rabbits similarly treated intravenously, no 

 precipitins were found at this time. They may appear a few 

 days thereafter and reach a high titer. 



(3) No anaphylactic manifestations occurred in rabbits treated 

 repeatedly with subarachnoid injections of normal horse serum 

 when the precipitin content of the blood was high. 



(4) Anaphylactic, as determined by passive transfer of 

 anaphylaxis, were demonstrated in sera with high precipitin 

 content. 



(5) These experiments may explain clinical manifestations 

 of intolerance to horse serum, observed when an initial intravenous 

 injection of antimeningococcic serum followed a series of intra- 

 spinous injections of such serum. 



5 (1587) 



Experimental gigantism produced by feeding pituitary gland. 

 By Eduard Uhlenhuth. 



[From the Rockefeller Institute for Medical Research, N. Y. City.] 



Growth of the individual stops, when the size is reached 

 which is specific for the species to which the individual belongs. 

 The causes which lead to the cessation of growth are not fully 

 known. In man it happens sometimes, that growth continues 

 beyond the normal maximum size of the species; this condition is 

 known as gigantism. Clinical evidence points to the conclusion 



