92 Rey. A. EH. Eaton’s Monograph 
Genus T'rRIcoRYTHUS. 
(Ala mesothoracica, Pl. II. fig. 3.) 
Ephemera, Sav.1817. Ceenis, Pict. 1843-5. Tricorythus, 
Etn. 1868. 
Imago. Ale duz; sete tres equales; oculi maris 
integri. A nervis alarum facillime e Ceni distinguitur. 
Tricorythus varicauda. 
Cenis varicauda, Pict. 1843-5. 
Imago, s.s.  Pallide luteus, vel ochraceus; oculis 
maculaque in vertice atris: suturis (?) mesothoracis dorsi 
quoque atris; alis vix flavescentibus, costis subcostisque 
paulo saturatioribus; et pedibus luteis vel ochraceis 
griseo variis. Segmentorum abdominis quinque apicalia 
punctis singulis ventralibus nigris. Set albz, anguste 
nigro annulate.”  (Pict.) 
Long. corp. ¢ 4, set. 9; exp. al. 10 mm. 
Hab.—Upper Egypt. 
Genus CNIS. 
Cenis, Ste. 1835-6. Brachycercus, Curt. 1834. Ma- 
crocercus, Westw. 1836. Oxycypha, Burm. 1839. Ceneus, 
Agassiz, Nomenclat. * 
(Ala antica, Pl. IT. fig. 4.) 
Nympha fodiens. Segmentorum abdominis 1, 3, 4, 
5, 6, 7 branchifera: laminarum antice minute, erecte ; 
secundee magne, crassz, ceeteras tegentes ; relique tenuis- 
sim, semiovate, bene fimbriatz, imbricate, graduatim 
minores a fronte retrorsum; omnes simplices. Pedes 
femoribus vel compressis vel gracilibus secundum 
speciem. Caput vel inerme, vel cornibus tribus fronta- 
libus armatum. Palpi maxillares tri-articulati: supe- 
rioris proximus articulorum largus, tertio longitudine 
* Brachycercus being a sexual name gives place to Cenis. Cenia, 
Newman, 1838, is a genus of Diptera. Conis was changed by Poseidon 
into an invulnerable man named Ceneus, one of the Lapithe. He being 
buried alive by the Centaurs in the course of the famous battle, was 
thereupon transformed into a bird. She somehow seems to have regained 
her original form; for Virgil narrates the meeting of Mneas with Cenis 
in Hades, in Ain. vi. 448. 
ER Sec 
