4 [June, 



Aiolacochilus aud the prest^nt genus. The type of the genus Megalo- • j 

 dacne is the ^^ccies fasciata, Fab., and it measures 17 mm., and some ' | 

 o£ the species are larger. Fig. 3 represents the sterna of Megalodacne 

 hellula, Lewis, from Japan. In Microsternus no species is known at j 

 present which measures over 7 mm., and 4 to 6 mm. is the average 

 length of the individuals now under examination. There are lateral 

 striga on the prosternum of AulacochiJus, shorter or longer in various 

 species, and in algerinus, Bedel, they converge at the apex, but in 

 violaceiis, Germ., the lateral strije are interrupted as shown in the 

 figure. 



Of course the almost total disappearance of the mesosternum in 

 Microsternus, and the comparative small size of it in AulacocJiilus, are 

 very important characters, and if systematists should hereafter con- 

 sider this structure one of superior value for classification, it will be 

 necessary to bring the genus Erotylus nearer to Megalodacne. At 

 present AulacocJiilus stands between Megalodacne and Erofylus, yet 

 the last two alone have a conspicuous mesosternum. 

 Wimbledon : April IZth, 1887. 



NOTES ON THE ENTOMOLOGY OF POETIJGAL.— IX. EPHEMEBID.'E. 

 BY THE EET. A. E. EATON, M.A., F.E.S. 



This Family of insects has hitherto received no attention from 

 Portuguese entomologists ; and the species here noticed were captured 

 for the most part on only chance opportunities. The list is, therefore, 

 unduly short : for unless a collector can make it his business to visit 

 suitable localities at the right seasons, and at times when the flies are 

 on the wing (which can only be done where quarters are obtainable 

 within convenient proximity to those places), he cannot thoroughly 

 investigate the May-fly fauna of a country. Neither spiders' webs, 

 nor nymph catching, can^fully compensate for his absence during the 

 hours of the flights. Some species, however, can be advantageously 

 collected in sub-imago earlier in the clay ; and a netsuian learns to 

 value a lantern if he stays out until nightfall in mountainous districts. 



Oligoneuria rhenana, Imh. — Nymph capti^red in the swift shallows above 

 Ponte de Morcellos. 



Ephemera glaucops, Pict. — A ? imago, caught in the evening at Sao Marcos da 

 Serra, was devoured by a moribund dragon-fly in the killing-bottle. There is a 

 specimen from central Portugal in Lisbon Museum. 



Leptophlelia, sp. ? — Nymph in a hill-stream west of Villa Eeal, Traz-os- 



Montes. 



Choraferpes Picfeti, Etn. [the CIi. Insitaulca of Ent. Mo. Mag.,xvi, 194 (Feb., 



