332 EEV. A. E. EATON ON EECENT EPHEMEEID.E OE MAYFLIES. 



Plate XVIII. 



Neuration, limbs, and external c? genitalia of 32. Coloburus {= Coloburiscus]; also external ^ genitalia 

 of 33. Chirotonetes, and limbs of 34. " Siphlurus?" [ — Ameletus] : — all enlarged. 



Figs. 33 a. C. humeralis : — wings ; legs (1-3) of c? and fore leg of ? ; partial underside view of forceps; 



underside of penis (dried) . 

 Figs. 32 b. A nameless N.-American CoJoburiscus : — hind wings and part of a fore wing ; legs (1-3) of ? 



(dried). 

 Fig. 32 c. C. haleuticus : — underside view of penis (dried) . 

 Fig. 33 d. Ch. siccus : underside view of the forceps-basis, with parts of the limbs, with parts of the 



penis-lobes in outline (dried) . 

 Figs. 33 e. Ch. aridus : — underside view of the forceps-basis, with parts of the limbs and a portion of the 



9th segment ; also (above the number) underside view of the extremity of the penis in outline, 



with dried exudation coarsely stippled (dried). 

 Figs. ?34a'. " S. ?femoratus" [ = A. subnotaius'] : — legs (1-3) of ^ and fore leg of ? (dried). 



Plate XIX. 



Neuration, limbs, external ^ genitalia, and ^ head of 33. Chirotonetes, and a 

 wing of 32. Coloburiscus : — all enlarged. 



Fig. 32. C. " halenticus" [for haleuticus] : — fore wing. 



Figs. 33 a. Ch. mancus : — wings only [the legs are wrongly lettered]. 



Figs. 33 b. Ch. ignotus : — both wings and part of a fore wing; legs [wrongly lettered 33 a for 33 i] (1-3) 

 of (J and fore leg of ? ; underside partial view of genitalia held aslant, showing a forceps-limb 

 and part of the forceps-basis with one and a portion of the other of the penis-lobes (dried) ; 

 vertical, front, and side views of adult ^ head (freshly killed). 



Figs. 33 ? c. Ch. ? ornatus (page 208) :• — underside view of forceps and of penis (dried) . 



Plate XX. 



Neuration and limbs of 34. Siphlurus, ? 34. Metamonius, and 35. Dipteromimus, with external ^ genitalia 

 of the first and the last genus and head of adult ^ Siphlurus : — all enlarged. 



Figs. ? 34 b. S. [^Metamonius'] anceps : — wings and legs (1-3) of ^ (dried) . 



Figs. 34 c. S. typicus : — wings. 



Figs. 34 f/. S. lacustris : — legs (1-3) of J' and fore leg of ? ; underside of forceps; vertical and side 

 views of adult ^ head (freshly killed) . 



Fig. 34 e. S. armatus : — underside view of forceps and part of segment 9 (dried). 



Figs. 35. D. tipuliformis : — fore wing and part of the hind wing; legs (1-2) of ^ , with a more enlarged 

 view of the intermediate tarsus ; side view and underside view of genitalia, showing the forceps 

 and the penis (dried). A complete figure of the hind wing is shown in PI. LXIV, 



Plate XXI. 



Neuration, limbs, and external ,^ genitalia of 36. Oniscigaster and 37. Bcetisca, 

 with head of adult ^ of the former : — all enlarged. 



Figs. 36. 0. Wakefieldi : — wings ; legs (1-3) of ? and fore leg of (^ : underside view of the genitalia, 

 with the 9th and part of the 8th segment, showing the right and part of the left forceps-limb, 

 and the shrunken penis ; head viewed obliquely from in front and also from the side (dried). 



Figs. 37. B. obesa : — wings; legs (1-3) of $ and fore leg of (J; underside view of the right forceps- 

 limb and the penis (dried) . 



