4 [June, 



Aulacochilus and the present genus. The type o£ the genus Megalo- 

 dncne is the species /«scifl^<7, Pab., and it measures 17 mm., and some 

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

 belJula, Lewis, from Japan. In Microstermis no species is known at 

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

 length of the individuals now under examination. There are lateral 

 striae on the prosternum of Aulacocliilus, shorter or longer in various 

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

 violaceus, Germ., the lateral striae are interrupted as shown in the 

 figure. 



Of course the almost total disappearance of the mesosternum in 

 Mio'ostermis, and the comparative small size of it in Aulacocliilus, 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 Aulacochilus stands between Megalodacne and Erofylus, yet 

 the last two alone have a conspicuous mesosternum. 

 Wimbledon : April 15th, 1887. 



NOTES ON THE ENTOMOLOGY OE POETUGAL.— IX. JEPHEMEEID^. 

 BT THE KEY. A. E. EATON, M.A., E.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 wang (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 day ; and a netsman learns to 

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



Oligoneuria rhenana, Imh. — Nympli captured in the swift shallows above 

 Ponte de Morcellos. 



Ephemera glaucops, Piet.— 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. 



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



Montes. 



ChoToterpes Picteti, Etn. [the Ch. lusUanica of Ent. Mo. Mag.,xvi, 194 (Eeb., 



