310 EEV. A. E. EATON OX EECENT EPHEMEEID^ OE MAYFLIES. 



Group III. (p- 199). At the roots of the mesothoracic wing the Anal 



(8) nei'A'urc is sejiarate from the Pobrachial (7) nervure, but a channel of circu- 

 lation is traceable between them in the wing-membrane ; the 1st Axillar, de- 

 tached from its own group of nervurcs, either meets or approaches the Anal (8) 

 nervure. Hinder tarsi distinctly 5-jointed 4 



2 . . . . Series 1 or Group I. (p. 22). Legs of ? short and feeble, when not 

 atrophied and functionless. Hind leg of ? longer than the fore leg. Eyes of 



c? evenly contoured 5 



Series 2 of Group I. (p. 47). Legs of ? all functional. Fore leg of 



? at least as long as the hind leg, and usually rather longer. Eyes of d evenly 

 contoured 6 



3 . . . . Series 1 or Group II. (p. 77). At the roots of the fore wing the Anal 

 (8) nervure approaches or meets the Pobrachial (7) and is met by the 1st Axil- 

 lar (9') which distally describes a bold curve. Eorceps-basis of J and lobe of 

 the 9th ventral segment of ? developed. Eyes of d evenly contoiu'ed ... 7 



Series 2 op Group II. (p. 81). At the roots of the fore wing the Anal 



(8) nervure is quite separate from the Pobrachial (7) : the 1st Axillar (9^) usually 

 describes a simple curve which is strongly arched distally ; but sometimes close 

 to the wing-roots, from certain points of view, it appears to be continued for- 

 wards along the crease in the wing-membrane so as to curve abruptly towards 

 the Anal (8) nervure, and then it may be termed ogee*-curved. Eorceps-basis 

 of 6 and lobe of the 9th ventral segment of ? developed. Eyes of d ascalaphoid 8 



Series 3 of Group II. (p. 136). At the roots of the mesothoracic wing 



the Anal (8) and Pobrachial (7) nervures lie close alongside of each other, or in 

 mutual contact, apart from the Axillar (9) nervures. Pra^brachial (G) nervure 

 forked. Eyes of <S evenly contoured aiul far asunder 9 



Series 4 of Group II. (p. 153). At the roots of the mesothoracic wing 



the Anal (8) nervure is quite separate both from the Pobrachial (7) and the 

 1st Axillar (9') nervure. The 1st Axillar nervure is gently curved, and the 

 Prsebrachial (6) nervure is essentially simple. Eorceps-basis of d and lobe of 

 the 9th ventral segment of $ undeveloped. Eyes of d divided into two unequal 

 segments ; the uj)per segment is large and turbinate, the lower small and oval . 10 



4 . . . . Series 1 of Group III. (p. 199). The Anal-Axillar interspace [in 

 Bcetlsca the 2ud Axillar space] of the fore wing includes the anal angle and 

 the outer half of the inner margin. The Anal (8) nervure [in JBtstisca the 2nd 

 Axillar (9')] is less curved than the 1st Axillar (9*) [in Bcetisca the 3rd Axillar 

 (9'^)], and its numerous branchlets meet the outer Ijalf of the inner margin . . 11 



Series 2 of Group III. (p. 229). Adult unknown 12 



* Ogee or ogive, an architectural term, signifies the sinuate curve shown in vertical section of the side of a vase 

 or cup that is rounded at the base and everted at the rim. 



