Blood glucose and l i v e r glycogen levels were determined in hypophysectomized, sham-operated and unoperated control animals a l l of which had been starved f o r 10-15 days.starvation causes a significant decrease in newt blood glucose and t h a t t h i s decrease i s not enhanced by hypophysectomy o r sham-operation during a 15-day period. These d a t a indicate t h a t e f f e c t s of short periods of hypophysectomy on regenerating t i s s u e s are probably not due t o a d r o p in available carbohydrate. However, the data do not indicate what the possible e f f e c t s of long-term hypophysectomy on blood gl ucose would be.The r e s u l t s show t h a t I t i s known t h a t hypophysectomy retards the regeneration of limbs and lenses in adult newts (Connelly e t a l . , '68; Tassava, ' 6 9 ; Connelly e t a l . , ' 7 3 ) . hormone therapy. might be due t o a reduction in the u t i l i z a t i o n o f energyreserves by operated I n the limb system the e f f e c t s of hypophysectomy may be overcome by There has been concern that the e f f e c t s of hypophysectomy animals. Since hypophysectomized newts do not e a t well a l l animals a r e rout i n e l y starved in such experiments. be unable t o u t i l i z e glycogen stores o r might deplete such stores a t a very rapid r a t e and thus r u n out of reserves before regeneration can be completed.The experiments described below were undertaken t o determine the e f f e c t s of hypophysectomy and starvation on newts over a period when postoperative mortality would be low.As a r e s u l t of hypophysectomy newts might 367