SCALE OBSERVATIONS OF THE SQUETEAGUE AND PIGFISH. 



307 



of Cynoscion regalis, nor, judging from the cuts in the papers of Hutton, Dahl, and others, 

 does it appear to be true of other species. If each annulus represented a year and 

 the circuli appeared at regular intervals of time, then the number of circuli could vary 

 but little in each band. In the third place, that annuli and circuli have nothing in 

 common is proved beyond doubt by the fact that the former may cross the latter. 

 The suppositions referred to are negatived by these observations, and it remains that 



\A0 

 130 

 120 

 I 10 

 100 

 90 



5 80 



70 



JS 60 

 E 



Z 50 



40 



30 



20 



10 



2 3 ii. S 6 7 a 9 10 II 12 

 Lenoths — mm. (Cifculi opproxltnotel/ /lornm. oparf) 



13 



14 



Fig. I. — Showing munber and distance apart of the circuli on a scale of the squeteague including two annuli. Dotted line 

 represents the expected curve of such a correlation if the annuli were groups of appro.^imated circuli. 



one annulus may be produced each year, but that it is not produced by retarded growth, 

 nor does it consist of approximated circuli. 



That the annuli do not represent winters, as contended by the previously mentioned 

 investigators, is verified by the observations on Cynoscion regalis as already noted. If the 

 annuli represented winters, then in July and August the number between the periphery 

 and the last annulus ought to be at least half the average number of circuli between any 

 two adjacent annuli. But the small number of circuli found points to May or June as 



