EEV. A. E. EATON ON EECENT EPHEMEEID.E OR MAYFLIES. 337 



maxilla and palpus, with torn muscular tissue attached to the stipes, x 70 diam. 8. Labium, 

 2nd maxillfe, and palpi, x 50 diam. 9. Dorsal view of tongue and paraglossse, x 50 diam. 



10. Fore leg, 11. Intermediate leg, 12. Hind leg, each x 50 diam. 13. Tracheal branchia of 

 the 3rd abdominal paii-, x 50 diam. (In fluid.) 



Plate XXXIII. 



Blastunts, sp. — Nymph. 



Figs. 1-19, all enlarged. — 1. Dorsal view of insect with defective set;e, of advanced grade, in a con- 

 ventional attitude. 2. Ventral view of head and body of the same. 3. Antenna, x 25 diam. 

 4. Exterior of labriim, x 30 diam. 5. Right mandible, x 45 diam. 6. Left mandible, x 45 

 diam. 7. First maxilla and palpus, x 45 diam. 8. Underside of labium, 2nd maxillae, and 

 palpi, X 40 diam. 9. Dorsal view of tongue and paraglossiB, x 40 diam. 10. Fore leg, 



11. Intermediate leg, 12. Hind leg, each x 13 diam. 13-19. Tracheal branchise of the abdo- 

 men (one of every pair) numbered successively from the foremost, all x 15 diam. (In alcohol.) 



Plate XXXIV. 



Choroterpes Picteti. Nymph. 

 Figs. 1-20, all enlarged. — 1. Dorsal view of insect of advanced grade. 2. Ventral view of head and 

 body of the same. 3. Antennae, x 25 diam. 4. Exterior of labrum, x 20 diam. 5. Right 

 mandible, with tendon attached, x 30 diam. 6. Left ditto. 7. First maxilla and palpus, 

 X 20 diam. 8. Point of the lacinia of the same maxilla reversed, x 60 diam. 9. Underside 

 of labium, 2nd maxillse, and palpi, x 20 diam. 10. Dorsal view of tongue and paraglossae, 

 X 20 diam. 11. Fore leg, 12. Intermediate leg, 13. Hind leg, all x 20 diam. 14-20. 

 Tracheal branchiae of the abdomen (one of every pair) numbered consecutively from the 

 foremost, all x 20 diam. (In fluid, from Portugal.) 



Plate XXXV. 



Tltraulus bellus. Nymph. 

 Figs. 1-22, all enlarged. — 1. Dorsal view of insect of very advanced grade, with the legs in a 

 conventional pose, but otherwise in a quiescent posture. 2. Ventral view of the head and 

 body of the same. 3. Autennee, x 30 diam. 4. Exterior of labrum, x 30 diam. 5. Right 

 mandible, with tendon attached, x 60 diam. 6. Left ditto. 7. First maxilla and palpus, 

 X 30 diam. 8. Point of the lacinia of the same maxilla reversed, x 60 diam. 9. One of the 

 pectinate spinules or bristles of the preceding, more enlarged. 10. Underside view of labium, 

 2nd maxillae, and palpi, x 30 diam. 11. Dorsal view of tongue and paraglossae, x 30 diam. 

 12. Fore leg, 13. Intermediate leg, 14. Hind leg, all x 20 diam. 15-21. Tracheal branchiae 

 of the abdomen (one of every pair) numbered consecutively from the foremost, all x 20 diam. 

 22. The foremost of these x 45 diam. (From Cintra, in fluid.) 



Plate XXXVI. 



Habrophlebia fusca. Nymph. 

 Figs. 1-24, all enlarged. — 1. Dorsal view of insect of advanced grade in repose. 2. Ventral view of 

 head and body of another specimen. 3. Antenna, x 25 diam 4. Exterior of labrum, 

 X 50 diam. 5 and 6. Right and left mandibles with tendon attached, x 65 diam. 7. First 



45* 



