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sendo riportata nei Proceedings essa sfuggì a tutti, e la trovo 

 citata una sol volta nel Catalogo dell' Hunter. Tuttavia io la 

 reputo della massima importanza dal punto di vista storico, 

 poiché contiene il primo accenno alla scoperta della metamorfosi 

 dei Blefaroceridi, su cui tanto venne scritto. Credo quindi op- 

 portuno riportare qui integralmente la breve nota. 



« The Secretary also exhibited a photograph on behalf of 

 Dr. Fritz Miilier, and read the following note: I thake the 

 liberty of sending you a photographic copy of some drawings 

 of a very curious dipterous insect. The larva is remarkable for 

 having six segments only, each beiug provided on the ventral 

 side with a complicated disk, by which it fìrmly adheres to the 

 rocks of rapida. The first segment of the larva is a cephalo- 

 thorax, comprising the head, thorax, and first abdominal segment 

 of the pupa. The pupa, which is firmly cemented to the rocks, 

 has its antennae, wings and legs free, not adherent to the body. 

 The perfect insect is remarkable for the dimorphism of the 

 females. One set of females agrees in the want of mandibulae 

 and the structure of the orai parts with the males. They are 

 probably honey-sucking. The other set of females are provided 

 with mandibulae, like the blood-suckings females of Culex, Ta- 

 banus, etc. In the size of the eyes and the structure of the 

 feet the blood-sucking females differ mudi less from the males 

 than the honey-sucking females do. I bave lately sent to the 

 "Archivos do Muséu Nacional de Rio de Janeiro" a description 

 of this insect, accompanied by seven plates, three of which 

 refer to the highly interesting structure of the larva ». 



1880. 



Nota. CoU'appressarsi del compimento del 2" ventennio, ecco 

 apparire in quest'anno il grande avvenimento della scoperta della 

 metamorfosi : vedremo quanta luce questa apportò sulle affinità 

 della famiglia. Assai notevole è poi il fatto che questa scoperta 

 sia avvenuta al Brasile. 



