Sir Philip Egerton on the Tail of Diplopterus. 53 



usually longer^ but sometimes a little shorter than the third : the 

 mouth is yellow with a black tip : the nectaries are black, and 

 nearly one-fourth of the length of the body : the legs are black ; 

 the fore-thighs from the base to the middle, the other thighs at 

 the base, and the shanks excepting their tips, are yellow : the 

 wing-ribs are yellow ; the wing-brands axe pale brown ; the veins 

 are brown. 



1st var. The abdomen is dark yellowish green ; there is a 

 row of short black bands along its back and a row of black spots 

 on each side : the mouth is black, but yellow towards the base : 

 the legs are black ; the thighs are pale yellow at the base ; the 

 shanks excepting their tips are dark yellow. 



The front is slightly convex : the feelers are seated on short 

 stalks ; the first joint is longer and more slender than the base 

 which supports it ; the second is shorter and much narrower than 

 the first ; the third is a little more slender than the second; the 

 fourth is much shorter than the third ; the fifth is shorter than 

 the fourth ; the sixth is about half the length of the fifth ; the 

 seventh is nearly as long as the third : the nectaries are spindle- 

 shaped : the tip of the abdomen is compressed, and rather more 

 than half the length of the nectaries : the fore-legs are much 

 shorter than the hind-legs, whose shanks are slightly curved : the 

 length of the furcations of the third vein is variable. 



Variation in the wing-veins. The lower branch of the first fork 

 of the third vein is wanting. 



[To be continued.] 



IX. — Observations on Mr. McCoy's description of the Tail of 

 Diplopterus*. By Sir Philip de Malpas Grey Egerton, 

 Bart. 



To the Editors of the Annals of Natural History, 



Gentlemen, 

 I ventured to trespass on your columns in September last, to 

 direct attention to what I considered an unfairness on the part 

 of Mr. M'Coy towards my absent friend Professor Agassiz. In 

 his reply to my observations Mr. M^Coy distinctly acknowledges 

 the priority of Agassiz^s observations, and allows that the know- 

 ledge of them " added considerably to the certainty which he 

 felt of the correctness of the view he had put forward.^^ The 

 courtesy usually observed between investigators in a common 

 field would have required this avowal to have been made in the 

 first instance. Though tardy it is nevertheless complete. I re- 



* Ann. and Mag. of Nat. Hist. Nov. 1S18, p. 303. 



