THE CANADIAN ENTOMOLOGIST. 207 



MERISTIC VARIATION IN CORYDALIS CORNUTA, LINN. 



BY H. F. WICKHAM, IOWA CITY, IOWA. 



Records of duplication of members in hexapod larvae are so rare that 

 I submit the subjoined account, drawn up from a specimen of the young 

 of Corydalis cornuta, captured in the river near Iowa City, several years 

 ago. The insect is one of a number that I took for class dissection, and 

 as far as noted, the remainder did not depart from the ordinary type. A 

 notice of the case was prepared at the time and sent to a scientific journal 

 on the eve of its suspending publication, so that I think the article was 

 never printed. 



The larva under discussion measures, in its preserved state, about an 



inch and three-quarters in length. The duplication of parts concerns the 



left hind leg, where the femur, which is normal, bears a bifurcate tibia, one 



branch of which is longer than the other. The longer side attains a length 



about equal to that of the right tibia, and bears a tarsus which is 



approximately normal, though the claws are nearer together than usual ; 



/»— V. the shorter side of the tibia supports a tarsus, 



I \ which in its turn shows a decided tendency to 



J \ bifurcation and carries two pairs of claws. 



Cl y^^>>_^ \ The proportions of the parts are shown in the 



/ I \ \ figure. (Fig. 8.) I am not certain that the 



^W \\ short tarsus is drawn in proper perspective, 



\ \ as I accidentally broke it off at the joint 



\ \ marked a in the figure, and may have twisted 



\/ it in replacing. The specimen is preserved in 



„. „ my collection. 



Fig-. 8. -' 



PREOCCUPIED NAME. 



I refer to Prof Fernald's kind notice of my " Hawk Moths," Can. 

 Ent., 98, 1887, for the statement that the generic term ^/';v?/j' is pre- 

 occupied, having been used by Koch in 1837 fo'' ^ genus of Scorpions. I 

 should not have troubled myself further in the matter of changing this 

 name in the Sphingidse, seeing that Prof Fernald believes a separate 

 genus {ox plebeia from Protoparce unnecessary, except that Rothschild and 

 Gordon, in their exhaustive revision of the Sphingidas, just published, 

 retain the name Atreus and criticise my calling the species ''■ plebehts" 

 instead of plebeja. So I change the name Atreus, Grote, 1886, to 

 Paratrea, with P. plebeja as type. A. R. Grote. 



