402 The Ohio Naturalist. [Vol. XII, No. 1, 



Paragus tibialis (Fallen). 



Larva. 



Length about 7.5 mm., width 2 to 2.5 mm., height 1.5 mm. 

 Similar in superficial appearance to the previously described 

 Paragus bicolor but slenderer and smaller. Color markings 

 variable. Ususally the heart line is rather prominent as is also a 

 similar looking dark line along each side of the body about under 

 the dorsal segmental spines. The reddish color is of much less 

 -extent than in P. bicolor and is largely replaced by a sulphur 

 yellow tinge. In some specimens the general color is unifomi light 

 yellowish brown. The segmental spines are shorter and situated 

 ■on smaller conical elevations than those of P. bicolor (Fig. 32), 

 but the dorsal one in segments (J to 11 is less reduced proportion- 

 ately, being about one-third as long as the median and dorso- 

 lateral ones. (See Fig. 31). 



The most convenient means of separation of the two species 

 in the larval stage is in the length of the posterior breathing 

 appendage. This in P. iibialis ranges from about O.-i mm. to 

 0.G5 or 0.7 mm., with an average of about 0.5 mm. as compared 

 with P. bicolor where the length is near 0.3 mm. The width at 

 the tip is about 0.25 to 0.3 mm. as in P. bicolor. The appendage 

 besides being distinctly longer is somewhat more bifurcate at the 

 tip in P. tibialis and the general surface is slightly more depressed 

 between the spiracular elevations. This will be made clearer by 

 reference to Figs. 25, 26, 33 and 34. 



Larvae were taken from common Burdock (Arctium minus 

 Schk.) at Lakeville, Ohio, June 21st;" at Sandusky, Ohio, from 

 July 30 to August 5; and at Kelley's Island, July 8th. They 

 were found on the upper, but chiefly on the lower side of the 

 leaves of Burdock parasitic in colonies of aphids (species unde- 

 termined) the body fluids and viscera of which they devour in 

 the usual manner. 



They were found parasitized to a slight extent by the 

 hymenopteron Bassus sp. 



Pupa: 



Dimensions, average of flve: length 4.3 mm., width l.S mm., 

 height 1.75 mm. Nicely rounded out anteriorly and dorsally, 

 flattened to the surface of the leaf ventrally and attenuated 

 strongly to the posterior respiratory appendage both by depression 

 and by compression (Fig. 35). The posterior appendage is very 

 frequently turned to one side or other from the middle line. 

 General color unifonn pale brown to darker, the six spiracular 

 elevations black. 



Compared with P. bicolor the puparium is less rounded up 

 posteriorly, more attenuated (Fig. 35, cf. Fig. 28). The characters 

 of the posterior, breathing appendage and the segmental spines 



