Fig. 5. Comparison of the total amount of light (L_tot) produced, as a response to 5-HT (0.03 mmol l^–1), between the different months when experiments were performed. Some specimens tested in April and June were very bright, hence the large mean value of L_tot and the large variation in response in these months. Number of replicates (non-converging data in brackets, not included in the analysis): Sept., N=8 (1); Nov., N=9 (1); Dec., N=10; Apr., N=14 (4); June, N=10 (1); Sept., N=10 (2); error bars indicate s.e.m.