nn: 1 M \ I \ I l LIE S'J \ it: OF CHE N.\ I A. 



11. EPITHECA PRINCEPS. R 



N Am. Neur., : 

 Selys, Syn. Cordul., p. 41. no. 24. 



Nympha raised by H.J.Hubbard, Detroit River, Micb., June 3, L874,in 

 very large numbers; also in alcobol, Cambridge, Mass. Peoria, [II., June 

 28, October 23; Pekin, Ql., October 9; Cedar Lake, III., October L2 and L8 ; 

 young, all from Prof. Forbes. Length, 26 mm. ; breadth, 13 mm. 



Body a little shorter but as broad as E. bimaculata, from which it differs 

 a> follows : conical tubercles less sharp ; palpus shorter, broader than long, 

 teeth on the edge, less pronounced ; abdomen shorter, length less than twice 

 breadth; lateral spines on segment 9 shorter, nn 8th very shorl ; anal ap- 

 pendages a little shorter than the last two segments, the laterals thicker; 

 the dorsal median enlarged above to the apical third. 



The nympha of E. princeps is easily recognized by its broader but shorter 

 body, the smaller tubercles on the head, and the shorter and straight lateral 

 spines on the 9th segment. The rectal part of the digestive tube is mostly 

 retained in the nympha skin in this species which is unusual. Two speci- 

 mens have an oval cocoon of a parasite fixed to the abdomen ; the parasite 

 itself has left through a little round opening, so it was doubtless a Hymen- 

 opteron. 



12. EPITHECA SPEC. 

 Plate IV. Fig. 3. 



Dry nympha from Central Illinois. August, from C. V. Riley ; a little 

 larger in alcohol, from Central Illinois, from Prof. S. A. Forbes. Length. 

 12 to 17 mm. ; breadth. 6 to 9 mm. 



Both nympha? are apparently not fully grown, as the genitals are not yet 

 marked ; very similar to E. princeps, but the two tubercles on the head are 

 much larger and more developed, erect, and form two conical horns. The 

 supposition that these nymphae may represent younger stages of E. princeps 

 must be dismissed. Nympha? of E. princeps of the same size, as well as 

 much younger ones, were examined, and did not differ from the adult. Be- 

 sides the marked difference in the size of the horns, the abdomen seems to 

 me larger. 



As many species are known, it is impossible to make a supposition. 



