Platelet aggregation response to adenosine diphosphate, epinephrine, norepinephrine, Russell viper venom, and collagen was studied in eight species of primates. Responses were generally qualitatively similar for each agent though they differed in intensity and in velocity among the various species. Phylogenetic patterns of similarity were not marked except in the nearly identical responses in the three species of macaques studied. Phencyclidine tranquilization did not affect the response.

Lactic dehydrogenase and phosphohexose isomerase activities in canine serum are directly correlated with the amount of hemolysate present as measured by hemoglobin content (r = 0.97 and 0.99 respectively). Very similar activities of lactic dehydrogenase and phosphohexose isomerase per gram of hemoglobin were observed. Mathematical analysis suggests that all lactic dehydrogenase activity of normal canine serum is due to imperceptible hemolysis. Inhibition of serum leucyl aminopeptidase activity was observed to be proportional to the concentration of hemolysate. No relationship or interaction between alkaline phosphatase activity and the concentration of hemolysate was observed.