EEV. A. E. EATON ON EECENT EPHEMEEID^ OE MATELIES. 109 



amber-coloured or subtestaceous. Wings vitreous, with light pitch-brown nervures ; the 

 marginal area of the fore wing contains about 11 simple and straight cross veinlets in 

 the pterostigmatic region, but none before the bulla. Length of body G, Aving 6-5 mm. 

 Ilab. Lahat, Palenburg, viii. 22. Communicated from Leyden by Mr. Ritsema. 



Thratjlus mexicanus, sp. nov. Plate XIII. 23* * (hind wing and genitalia). 

 Calliarcys (provisional) mexicanus, ! Etn., iu the writing of the plate quoted. 



Imago {dried), 6 . — Thorax fuscous above. Abdomen white, with segments 8-10 and 

 the apical margins of segments 2-7 fuscous. Setse white with black joinings. Fore 

 wings vitreous ; 10 slightly curved and mostly simple (rarely anastomosing near the 

 costa) cross veinlets exclusively in the pterostigmatic portion of the marginal area of the 

 fore wing. Length of body 6, wing 7, setie 15 mm. 



Sab. Mexico (Brussels Mus.). The neuration of the fore wing conforms to the type 

 of the following species. 



Thraulus, sp. . Plate XIII.* - (wings). 



Calliarcys (provisional) sp. , ! Etn., in the writing of the plate quoted 



A nameless species represented by two ? subim. (M°Lach. Mus.), communicated by 

 Messrs. Godman & Salvin, has well-defined cross veinlets in the marginal area of the 

 fore wing both before and beyond the bulla. 



Rab. Irazu, Costa Rica, at an altitude of 6000-7000 feet (H. Rogers). 



Thratilus lepidus, sp. nov. 



Imago [dried), s . — Thorax rich brown-ochreous above, changing in some lights to raw- 

 umber brown. Abdominal segments 2-6 transparent whitish, each with the tip and an 

 oblique stripe on each side recurrent therefrom, fuscescent ; segments 7-10 rich brown- 

 ochre, lighter or pale yellowish ochreous towards the sides and beneath, and narrowly 

 edged with black at their distal dorsal border. Forceps light dull yellowish ; the limbs 

 inserted rather near to one another upon the basis, whose lower edge is only slightly 

 prominent in the middle ; the upper distal margin of the forceps-basis is prolonged into a 

 prominent rounded lamina about half the length of the penis : peuis hidden by dirt in 

 the type specimen. Setse white, with some of the joinings nearest the roots piceous, and 

 others in the remainder of the seta black, viz. towards the base of the seta every alternate 

 joining, about the middle of the seta every third joining, and beyond the middle of the 

 same every fourth joining. Fore leg in opaque view, with the femur, tibia, and joints 3 and 

 4 of the tarsus pitch-brown, the remainder of the tarsus dull light yellowish ochreous, the 

 tip of the tibia slightly tinged with pitch-black. Hinder legs in opaque view, with the 

 femur light reddish brown or rufo-piceous, tlie tibia and tarsus opaque amber-yellowish. 

 In transmitted light the dark portions of the legs are translucent rufo-piceous, the lighter 

 portions translucent yellow-amber. Wings vitreous, their neuration and the submarginal 

 area of the fore wing varying in colour with change of light from pitch-brown to raw- 

 umber brown ; the cross veinlets interjacent between tlie costa and the first half of the 



SECOND SERIES. — ZOOLOGY. VOL. III. 15 



